Yes, there's
some interpretation, but I addressed those points in my post. Also no, there's more information in the opening post than just "two female aliens". One can reasonably glean and infer more from the tags
IllRepute was looking into and what is present in the sample image.
I don't know why F95 modified the general usage of the Monster Girl tag, but most sites and how people generally interpret it is like this...
Anything that is not a human, alien, angel, robot, demon, animal, vampire, fairy, elf, or furry.
Whereas
aliens here is defined as: "Any character with strong characteristics meant to evoke a being of non-Earth origin. Typically humanoid in shape and lacks features from any real or mythical creature (e.g. eye stalks, no irises, bulbous head, tentacular body parts)." Not to be confused with Monsters; and a non-standard skin color or informed attributes alone will not quality to earn the tag.
As such, and
by and large and what most people generally agree to,
Aliens fall under Sci-Fi (and is even categorized as such in
real world libraries and by media providers/producers when it comes to subject matter on their books, movies, games, and so forth). Monster Girls, on the other hand, lean more heavily towards spheres of
Fantasy. Girls that are monsters with human features is the broad definition of it. Generally speaking, it applies when a work humanizes anthropomorphic monsters
girls. Sci-Fi works
can have Monster Girls, but aliens alone -- especially humanoid ones -- is not enough to warrant the latter tag.
I said my peace. This is
generally viewed as the
standard take for those tags. If you disagree, then that's fine. I don't want to argue (with you,
baloneysammich) and people are free to reinterpret those tags however they want. After all, all words including how tags are defined are all made up, but most folks generally agree with what those words (and tags) mean. Be safe and cheers.