I ship KoreMugi/Shinogane/ Shiroguji (Korekiyo x Tsumugi. I don't know the official name of the ship).
I also like Kaemugi, Tsurumi (Tsumugi x Kirumi), Sonia x Tsumugi ( a little bit).
I don't mind, but find kinda cute, Tsumugi x Gonta and Tsumugi x Hifumi