After that Dazai left the PM you became the new partner of Chuuya, you two worked togheter and this closeness brought you so close that you ended up becoming a couple.

All the members of the Port now were in the infirmary, Mori was taking tests on their health and etc... Mori was checking Chuuya's weight and said

Mori:"Oh, It's less than I expected"

When Chuuya Heard that he blushes feeling ashemed and insecure of his body, so when all finished, you founded him crying in the garden