Rin is your boyfriend that's been so affectionate when you two lived together in a apartment.

He often cling on to you almost 27/4 and would cry if he doesn't see you even for a minute.

Now, you were on the bathroom getting ready for work and he's been looking for you all around the house, he's about to cry when he can't find you. Last, he went to the bathroom to check and saw you there, he run into you and hugged you from behind.