It was a manga consisting of oneshots. In one of the stories, there's two brothers: one's a perfect student, the other's a deliquent. The rebel brother gets kidnapped by another student and is tied up and force into sex. In the middle of the scene, his brother comes in. The brothers end up having sex(obviously). In the end, however, the rebel doesn't remember anything afterwords.

If you could give me the name of the manga, that'd be great! Thanks! I've been trying to remember the title forever 😢

is it koiyami archive?

Thank you so much! ^.^