sussy age gap between high schooler and working adult
Manga
sussy age gaps between high schoolers and working adults. varying levels of sussy-ness, in terms of both the actual relationship between the two characters & how others within the story react to their relationship. listed in order of how sussy i personally find them to be, with both some at the bottom since i can't remember how sussy they are and some which are not high school.

Manga, 7 vol, 2019
Me:-
Author:8
Actual relationship: SUSSY
Other characters' perspectives: SUSSY
(Male) Adult's occupation: Salaryman
Other characters' perspectives: SUSSY
(Male) Adult's occupation: Salaryman

Manga, ? vol, 2011
Me:-
Author:-
Actual relationship: SUSSY
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Teacher
*Special note: BL
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Teacher
*Special note: BL

Manga, 8 vol, 2016
Me:-
Author:-
Actual relationship: Sussy
Other characters' perspectives: Not sussy
(Male) Adult's occupation: Salaryman
Other characters' perspectives: Not sussy
(Male) Adult's occupation: Salaryman
Yumemiru Taiyou
Dreamin' Sun

Manga, 10 vol, 2007
Me:-
Author:5
Actual relationship: Sussy
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Landlord
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Landlord

Manga, 1 vol, 2013
Me:-
Author:6
Actual relationship: Sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Erotic novelist
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Erotic novelist

Manga, 14 vol, 2015
Me:-
Author:6
Actual relationship: Sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Author
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Author
Tonari no Otona-kun
My Darling Next Door

Manga, 5 vol, 2020
Me:-
Author:7
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Salaryman
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Salaryman
Sensei wa Koi wo Oshierarenai
The teacher can not tell me love

Manga, 7 vol, 2018
Me:-
Author:4
Actual relationship: Somewhat sussy
Other characters' perspectives: Somewhat sussy
(Female) Adult's occupation: Teacher
Other characters' perspectives: Somewhat sussy
(Female) Adult's occupation: Teacher
Hige wo Soru. Soshite Joshikousei wo Hirou.
Higehiro: After Being Rejected, I Shaved and Took in a High School Runaway

Manga, ? vol, 2018
Me:-
Author:-
Actual relationship: Not that sussy
Other characters' perspectives: Sussy
(Male) Adult's occupation: Salaryman
Other characters' perspectives: Sussy
(Male) Adult's occupation: Salaryman

Manga, 16 vol, 2018
Me:-
Author:-
Actual relationship: Somewhat sussy
Other characters' perspectives: Somewhat sussy
(Female) Adult's occupation: Unemployed
Other characters' perspectives: Somewhat sussy
(Female) Adult's occupation: Unemployed
Hatsukoi Shinjuu
First Love Suicide Pact

Manga, 3 vol, 2013
Me:-
Author:1
Actual relationship: Somewhat sussy
Other characters' perspectives: Can't remember
(Female) Adult's occupation: Teacher
Other characters' perspectives: Can't remember
(Female) Adult's occupation: Teacher

Manga, 12 vol, 2007
Me:-
Author:4
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher

Manga, 1 vol, 2012
Me:-
Author:6
Actual relationship: Somewhat sussy
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Author
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Author

Manga, 16 vol, 2007
Me:-
Author:6
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: School janitor/hacker
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: School janitor/hacker

Manga, 15 vol, 2013
Me:-
Author:7
Actual relationship: Somewhat sussy
Other characters' perspectives: Not sussy
(Male) Adult's occupation: Salaryman
*Special note: may not fit in this list 100%
Other characters' perspectives: Not sussy
(Male) Adult's occupation: Salaryman
*Special note: may not fit in this list 100%

Manga, 10 vol, 2016
Me:-
Author:5
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher/Cooking club advisor
*Special note: several love interests, 2 of which are sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher/Cooking club advisor
*Special note: several love interests, 2 of which are sussy

Manga, 17 vol, 2008
Me:-
Author:6
Actual relationship: Not that sussy
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Teacher
Other characters' perspectives: Somewhat sussy
(Male) Adult's occupation: Teacher
Hirunaka no Ryuusei
Daytime Shooting Star

Manga, 12 vol, 2011
Me:-
Author:10
Actual relationship: Not that sussy
Other characters' perspectives: Varying from SUSSY to not sussy
(Male) Adult's occupation: Teacher
Other characters' perspectives: Varying from SUSSY to not sussy
(Male) Adult's occupation: Teacher

Manga, 6 vol, 2017
Me:-
Author:5
Actual relationship: Not that sussy
Other characters' perspectives: Sussy
(Male) Adult's occupation: Sales/writing
Other characters' perspectives: Sussy
(Male) Adult's occupation: Sales/writing
Koi wa Ameagari no You ni
After the Rain

Manga, 10 vol, 2014
Me:-
Author:-
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Restaurant manager
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Restaurant manager
Yakumo-san wa Ezuke ga Shitai.
Beauty and the Feast

Manga, 11 vol, 2016
Me:-
Author:6
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Housewife/widow (unemployed)
*Special note: Bonus age gap with deceased husband
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Housewife/widow (unemployed)
*Special note: Bonus age gap with deceased husband
P to JK
My Boy in Blue

Manga, 16 vol, 2012
Me:-
Author:2
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Policeman
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Policeman

Manga, 29 vol, 2007
Me:-
Author:8
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher
*Special note: Not primarily a romance
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Teacher
*Special note: Not primarily a romance

Manga, 3 vol, 2013
Me:-
Author:5
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Office Lady (OL) (?)
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Office Lady (OL) (?)
Takane to Hana
Takane & Hana

Manga, 18 vol, 2014
Me:-
Author:6
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: CEO
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: CEO
Shiawase Kissa 3-choume
Happy Cafe

Manga, 15 vol, 2004
Me:-
Author:5
Actual relationship: Not that sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Baker
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Baker
Coffee wo Shizuka ni
A Cup of Coffee.

Manga, 5 vol, 2019
Me:-
Author:-
Actual relationship: Not that sussy
Other characters' perspectives: Not sussy
(Female) Adult's occupation: Coffee shop waitress/owner
Other characters' perspectives: Not sussy
(Female) Adult's occupation: Coffee shop waitress/owner

Manga, ? vol, 2002
Me:-
Author:8
Actual relationship: Not sussy
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Actor
*Special note: Not primarily a romance. Also, Kyouko rarely ever attends school as she is working as an actress
Other characters' perspectives: Not that sussy
(Male) Adult's occupation: Actor
*Special note: Not primarily a romance. Also, Kyouko rarely ever attends school as she is working as an actress
Kore wa Koi no Hanashi
This Is a Love Story

Manga, 11 vol, 2010
Me:-
Author:-
*Special note: She's not in high school, she's 10...
Actual relationship: SUSSY
Other characters' perspectives: ?
(Male) Adult's occupation: Author
Actual relationship: SUSSY
Other characters' perspectives: ?
(Male) Adult's occupation: Author

Manhwa, 6 vol, 2019
Me:-
Author:4
*Special note: He isn't in high school, but the timeskip goes from him as a young child to him as a high school-aged duke so I'm making an exception cuz it's pretty sussy
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Maid
Actual relationship: Somewhat sussy
Other characters' perspectives: Not that sussy
(Female) Adult's occupation: Maid
Taiyou no Ie
House of the Sun

Manga, 13 vol, 2010
Me:-
Author:4
I remember this being somewhat sussy.
Older Male/Younger Female
Older Male/Younger Female
Yamada to Shounen
Yamada and the Boy

Manga, 1 vol, 2013
Me:-
Author:6
Actual relationship: Somewhat sussy
Other characters' perspectives: ?
(Male) Adult's occupation: Salaryman(?)
*Special note: BL
Other characters' perspectives: ?
(Male) Adult's occupation: Salaryman(?)
*Special note: BL

Manga, 1 vol, 2013
Me:-
Author:5
I remember this being not that sussy.
Older Male/Younger Female
Older Male/Younger Female
Tatoe Todokanu Ito da toshitemo
If I Could Reach You

Manga, 7 vol, 2016
Me:-
Author:-
*Special note: GL