Squall

Chapter 1: Protagonist has relations with his sister-in-law and there is more to it than just that.

Chapters 2-5: Protagonist's apartment building burns down and we follow him on his journey to find a new place to live.

Chapter 6: A brother & sister's surprising relationship is revealed to the brother's friend who joins the fun.

Chapter 7: The best childhood friend situation ever - three girls and one guy.

Chapter 8: This track team has an interesting training regimen where the guys keep the girls in "shape."


Source: mangaupdates