So, I decided to come back to this but with more evidence.

This ship is seen as bad, because Iroha is 15 and Yachiyo is 19.

I do admit, that's pretty weird, but... that's Japanese culture.

Iroha is pretty mature, and this game teases at their relationship like teasing a dog with food.

They built up a good relationship too

And this

It's an adorable relationship!

It's well written, and could be seen as friends, sisters, or lesbians.

4 isn't much of an age gap either.

Aphmau x Aaron, as much as I hate it, has a 4 year age gap and nobody seems to care, and that's American culture.

So. I rest my case. It's a good ship, and I don't count it as pedophilia. (I now do)

Edit: