When Deku gets overwhelmed, he instinctively shifts into his animal form. It’s easier for him to move around like this, especially with the weight of his large, round belly. Katsuki absolutely loves seeing him like this. He can’t resist cuddling up to Deku, his belly both soft and firm under his touch, he always love to soothing their pups specially when they are active inside.
Todoroki and Iidas pup love to hang around Izuku, he obviously cannot wait for his new playmates to be born.