Everyone be talking about how mitsuki would be sad if sousuke died, but if he did, no one will make mitsuki stay anymore. He would just go back to his life cycle, become a baby and forget everything.
I also think that mitsuki only affected sousuke's uncle's choice in love. Remember him saying about true love and stuff? So I think the uncle only ran after the girl he loves since mitsuki was just a person their dreams...
Well that's my theory hehe
It's gonna be all weird once Sou ages and Mitsuki doesn't though from "cousins" to "father and son" to "grandfather and grandson". And yeah, Sou's uncle took the dream as a sign to choose the woman of his life instead of his rich family.
Kalego joining the students and painting his nails as well HAHAHAHAHAHA BEST TEACHER!