Help me find this bl manhwa!

All I remember is that it had a side story where the main characters best friend, with white long hair wanted to get revenge on his friends ex(short red hair with side burns and an anger issue)who was one of those sex enthusiasts and had a group of friends just the same. MCs friend had sex with the ex(ex bottomed) and really liked it. The ex comes crawling back to the mcs friend but the mcs friend ends up ditching him to go on a date with a girl.