so "incubus" means someone who lies on top of something, and "succubus" means someone who lies underneath something, and the former also turns up in the word "incubate", which means to lie on top of an egg. To ensure closure we could therefore posit an analogous term "succubate", which would be something like this: Photo of a white and tabby cat with an egg balanced on its head he is succubating
https://s3.masto.ai/media_attachments/files/109/774/132/604/663/956/original/eb5982fffb62bd82.jpg