I love the idea of omega Izuku and alpha Katsuki only having alpha children.

They are all super protective and possessive of Izuku. They even work together to ward off their alpha father.

“You little brats! I had Izuku first! I am his mate!”

“He’s already had to carry five of your hell spawn give him a break old man.”

“You are my hell spawn!”

Katsuki does finally get some alone time with Izuku which results in a 6th and final child.

“We leave for one night and you couldn’t keep your grubby paws off our mom?!”

This time it is an omega.

The alpha brats switch their attention to the youngest now.

Katsuki is allowed to be around his mate but they never let him hold his baby.

“We don’t want you giving a bad example of how an alpha treats their omega old fart.”

“I’ll kill you!”

“Kacchan...”