I remember it's a manga with lots of one shots in them of the main story I think, it's where the same is in love with another guy that already has a bf (this story has many side characters), and is just sleeping with the use who really likes him. When a concert comes up he gives the use the ticket later asking for it back to give it to the guy he liked.
Can't remember this manga! Please help! And any other manga with many one shots in them
Thank you

Myuzu no Gakuen de Aou

Thankyou so much!