My Imouto: Koakuma na A-Cup

Both of them have cute "imoutos" (Little sister). Both are hentai. If you like one of them, i'm sure you'll like the other one too.  

-koi kaze anime, imouto hentai -younger sister falls in love with older brother -both take their sister shopping 

Lonely? A little sister is all you need. You probably already know what imouto means, so you already can tell what both of these OVAs are about, cute sisters loving their big brothers (maybe a bit too much), the relations between the siblings in both cases are very different, but they both have lovely and cute moments between siblings, in My Imouto the female protagonist is a tsundere, while Baka Na Imouto is bakadere (I'm making that one up). If you think that incest is wincest you should definitely watch both. 

hentai incest of older brother younger sister brother avoids sister though sister loves him and it all works out 

The main character in "Tsun Tsun" actually has posters of "My Imouto" in his bedroom. They are produced by the same company, have very similar art styles, cater to certain fetishes (little sisters and maids) in similar ways, are both 2 episodes of only 15 minutes long each, and they are both about just one guy and one girl coming together and having sex several times. 

Incest and cuteness. 

Titles are hentai genre and they focus on the romance between the heroine and protagonist with a few interferences. They both also contain Pettanko/Loli girls and are portrayed in a light-hearted tone, and receive a happy ending regardless of the interferences. Their school life is portrayed in the process. If you enjoyed one of these series for the characters, then you will enjoy the other as both are similar in some way. 

Incestuous sex scenes with a flat-chested little sister.