So We Can Scratch Issun, And Possibly Waka. Which Leaves only Oki or Herself.
That where it's get stumped. I mean, Yeah, She could have reproduced without........ "Mating" but Oki and Ammy have so kind of Spark, They Click Together. He really cared about her but we don't know how far that went.
Sadly, Only Capcom knows, unless Capcom doesn't even know himself. -_- Then That would Suck and That would mean We would have to ask Ammy herself but We can't, She ain't real -_-