Heroines of my Story!

Izuku Midoriya, 16, he is an otaku and a game developer and a hero in training, he is currently, on a break from UA, both of his crush admitted to be attracted to one another (Momo and Ochako) later, the same day they announced their relationship, Izuku heard a knock, when he opened the door to see Momo and Ochako, they asked him if he can be the donor, if they want to have a child , they also said that he was the one they trust enough and they don't want the donor to be unknown to them, he just smiled and said yes , he wants to forget about it, in the meantime... He got out of his house and walk to the park, he sat down at a bench and looked up to the sky, unknown to him, Four beautiful girls are looking at him...

They have were looking at him, as if he was their favorite food, they looked at each other and nods.

But...

Ochako and Momo, had a different reason on why they want Izuku to donate his sperm... It's not a bad reason, but a good one, can you guess on what it is?