I love when Mo starts trembling like that. He's so cute. (=・ω・=)
I wonder if he's acting like that cuz he tain kissed him so he's self conscious, or he's just acting like he hates it because he refuses to accept he likes he tain, hopefully we find out soon, them other two had their cute confession thing so hopefully the same happens to mo and he tain although with they have a really different dynamic to their relationship
I think it's because Mo really cares about hygiene. Remember one episode when he stopped He Tian drank his water because he didn't want his saliva on the bottle mouth, his word "it's disgust me to death".
He Tian knew about it, so he deliberately put a lot of saliva on the fork before gave it to Mo. Poor him! He Tian always tease him. But, well, we enjoy it anyway XD
I think it's the " indirect kiss thing " ;)
And He Tian is making fun of him, because put extra salvia on it , like a kid.
*saliva

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