I want the story of the other dude in the side stories.....pls🙏🙏🙏

"Lust" is about the black haired guy

Is there a link?

Yep, got to know that by reading the comments below..thanks for letting me know
ε=ε=(ノ≧∇≦)ノ

https://www.mangago.zone/read-manga/lust_2/

How are the two stories connected?

Not connected, this story is Abt seme's elder bro and his lover. Elder bro is seen in the side stories here...