100% Pascal-sensei (TV)

Wacky cartoon with perverted jokes and a weird plot that also exists sometimes 30-sai is more sexual than 100% pascal sensei and has not the greatest animation but if you want more nonsense jokes with even more nonsense characters check it out 

Both shows to do with school and contain a variety of characters belonging to a specific character trope making the characters interesting and colourful. The main student in both are the tsukkomi (straight man) characters of the anime so both shows have quite fast paced tsukkomi action. The premise of Mairimashita! Iruma-kun is different than 100% Pascal-sensei in that one consists of a human student living among demons and the other one an alien teacher living among humans. Iruma-kun is more story driven and Pascal-sensei is more gag-based with episodes split into parts (but still has a bit of a plot behind the scenes) but the main target audience for both anime are children. If you're looking for something fun and humorous with a lot of tsukkomi action, I highly suggest one and the other. read more 

Both episodic anime aimed with the demographic of children and are mainly comedies in genre. They each have fantastical characters where in Kingyo Chuuihou! there is a pink floating goldfish and cows that study at the school, all of which are able to talk the human language as well and 100% Pascal-sensei has Pascal himself (an alien) and Kitada who is a fully functioning boy robot partaking classes too. There is a lot of random stuff going on with the two each episode in the classroom but I like to think comparing the conventions of the two is like seeing how the genre of kids school-set anime has changed, despite both still being rather fun and hyper in activity too. read more