Blue's manga / #collection of stories(4)

I own this volume and it's one of my favorites but I really dislike slutty characters especially ones that act proud of what they have done. Having several lovers in the past isn't a bad thing but shoving it in the face of your lover that you've had a lot of random hookups seems cruel. The main story is the reason I bought the manga. One of the stories is a side story to another manga by the same author.