Basically this isnt on nhentai im pretty sure but I still thought to give it a try, it starts with the mc and his bestfriend walking into his house. Upon entering, the mc sees his bestfriends sister sitting on a chair at the dining table, where he slightly stares at her ass. Afterwards she gets up and greets him as it was long since they saw each other. Then the mc goes to sit on the couch and his friend asks him if he wants anything to drink, he says yes and the friend goes to get it. Meanwhile the sister comes to sit on the couch, starts talking about how he liked her back then, pulls his pants down and she gives him a bj. Just as the friend is about to enter she quickly gets up and says to mc to go to her bedroom. Afterwards he says to his friend that he has to go to the toilet, and as he goes the sister is at the top of the stairs waiting for him and inviting him in her room when then they do the thing.
Idk how I remember all this but I do, i cant seem to remember the name of it or the author and would appreciate help.