To help you locate the specific images:
Other players have mentioned missing images for certain characters; please refer to their comments for details.
Wendy’s belly is supposed to grow larger after the player gives her food gifts, but the first dialogue image remains unchanged—showing her standard "family-style" sprite. Similar issues exist with some other characters.
Even when living with the player, Wendy still treats the room as her own and kicks the player out.
There is a location in the Dream Kingdom that lacks a background image.
Items:
Inspecting "W-Medicine" in the inventory causes an error.
Uterine Stimulation:
Amanda displays a sprite without the pregnant belly.
Wendy’s value for this stat is completely reset to zero.
Rox and others do not have this attribute.