>>283279804
When developing pokemon diamond and pearl (Gen 4), the developers wrote down their ideas. One of those ideas was folklore where people fucked pokemon. Eventually this was scaled back, and only a few traces of it made it into the games, but the originals did leak, and that's why tyhplosion will never be officially acknowledged again.

In the lore documents that leaked, there were several stories where human x pokemon pairings created babies, and all the pokemon involved were either in the field egg group or the water 1 egg group. Egg groups in the games determine what pokemon can make eggs with what other pokemon when left at the day care, and a pokemon can only have 2 egg groups max, so the implication of the unreleased lore documents is that humans are not in the human-like egg group. They're more compatible with Octillary than Mr. Mime or Sawk.