Dragon_Samurai said: no the tag belongs there for obvious reasons. not everything has to be so textbook when it comes to tagging. some common sense should be involved with tagging. and with that the overflow tag fits considering what's going on in the picture.
Tags are meant to be applied as they are described for a reason. Certain tags aren't meant to be used literally in all instances. For example, you shouldn't use cowgirl for when a girl is on top, because that is reserved for girls dressed as cowboys/cows.
Some people may want to search for pictures where the cum is overflowing while the girl is being ejaculated into. So, a tag was made to describe this phenomenon. It was "overflow". There was no more specific word for it. So, in theory, a person searching overflow will recieve only picks where that certain situation is happening.
I think that cumdrip is good enough at describing what is going on here, but you win for now. I'm not going to remove it just so you can add it, again.