Kurabu e Yōkosu
[BTW, I recommend you to read Isshou Senkin, aside from being a good manga, there are a lot of context in that manga which will help you a lot, plus it's only 22 chapters, so PLEASE READ IT]
Hiroki who discovered the betrayal given by Nao, her sister, her mom and then Ayumu. It was all due to that bastard of a foreign exchange student....so he ran away, ran away from his family and everything which only gave him bad memories. After running away, he sulked in the corner of a bar...until two tired eyes caught him.
However this all changed when she meets 3 women who actually took their time to listen to his story and help him out slightly.
[This is a cross-over story between the shitty doujin Kokujin no Tenkousei and Isshou Senkin, a really great manga written by the author of Kengan Ashura, Kengan Omega and How Heavy are the dumbbells you lift?]
[Kengan Ashura is a Japanese manga series written by Yabako Sandrovich and illustrated by Daromeon. It was serialized on Shogakukan's Ura Sunday website from April 2012 to August 2018]