But I rather them be a pair because whatever happened in the future, Tsugumi give his consent and Megumi is aware of his responsibility. Eventho they are babies, at least they are aware of their decision. With how irregular Tsugumi's heat is, the chance he is bitten accidentally is really high and it is actually almost happened. And if that happened, it will be a lot more awful than any other possible break up scenario may happened in the future
Aside from what Inami said, I already feel anxious when Megumi didn't bite Tsugumi even after Tsugumi give his consent. The almost bitten accident is the prime reason as to why I wish he just bit Tsugumi, especially knowing how irregular Tsugumi heat is. I know he wants to do it properly and yada yada but how about left that part for the formal marriage and just make Tsugumi your partner already damn it