
I think Taehan was feeling conflicted, he was in a rut so he was scared he accidentally made Doyun pregnant when they werent into such a commited relationship yet, but on the other hand he kinda expect a baby/? And when Doyun mentioned marriage, Taehan probably didn't expect Doyun to be serious about it (well in the 1st place they were faking...)
Sensei i admire ur art so much ㅠㅠ