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