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I think the mantle is too long in proportion to the arms and is likely a smaller species but the eyes in the gif are very reminiscent of vulgaris. More photos will help. Even though a few species are relatively easy to ID, at any given instant, one octopus can show characteristics of many different species. Over a series of images we can usually make a decent guess.
And just to put this out there she is in a QT. Until She gets big enough for the other tank. I got a couple Fish in there that nip the Arms. Just thought I would clarify before people wondered why there are two different looking tanks
Look at O. digueti. I think the sizing and the eye papillae are a better match but would mean that she came from Southern California or Mexico.
I see no suggestion of a hectocotylus so agree with your feminine pronoun. At the end of her natural life, she will lay and brood eggs even if she has not mated. However, she appears old enough to have mated so you may have to opportunity to see eggs hatch and potentially raise one or two hatchlings. The chances of raising them are slim, regardless of egg size, A few dwarfs lay larger eggs that are not pelagic so the adventure will be interesting and I hope you will journal the full experience.