Its something called 'soft vore'.
Here are examples of it:
[link][link][link]Now, that drawing is one of the only drawings of Len as the "pred", as in him eating the shrunken person. Could commish you to do a drawing of him 'eating' someone? Doesn't have to include internal shots, however they would be nice! Only 2 drawings of him as pred, and that one makes him look too young, the other makes him look too old. So if you could try it, that would be awesome~~! I understand if you don't want to though, quite a few don't. Thanks anyways (This is Len Kagamine btw-vocaloid-age 14.)