Scrolling the posts in half-erect, I honestly would just tag a lot of those posts erect. If a character has a big penis, there really isn't much difference between a fully erect and half-erect state. Same for characters with a smaller size penis, half-erect would overlap with the flaccid tag. Unless the same character is drawn multiple times in various stages of erection, it's really hard (haha) to gauge just how "erect" a penis is.
Just feels to me like this tag is a bit too subjective/vague.
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