Yeah, this is extremely generic. Lotta soul-sucking/self-reviving monsters like this in videogames and TV series.
collects the "souls" from living beings, these souls are essentially all the energy from a human's body.
Why just humans? Also, there's no solid scientific explanation for this sort of "soul"/"life energy" substance stuff, and it sounds like something out of an anime or something. If you really want this to stand a chance on the mainsite, you're going to need to make sure the empirical science background is more believable.
Keep in mind that as the author, you know the entire story, but the Foundation needs to have discovered what it knows about the SCP object through observation and experimentation. You'll need to convince your reader that someone with no prior knowledge whatsoever of the anomaly managed to somehow figure out (not magically know!) all the information you've got in the article.
Most researchers who see this thing interacting with prey aren't likely to think "it's gotta be taking their souls, man".
It's main purpose is to reproduce and create more of itself, as well as resurrecting it's young (also created via asexual reproduction).
Why though? Is it just like a virus or something? What's the point?
Overall… not too sure about this. Seems pretty similar to most of the lowkey monsters we see deleted from the site almost every day. What makes this different from video game bosses with the same gimmick?