A common typo. This can probably be removed from any image.
Tip: you can look over the tag history to check if any words that were accidentally broken apart while editing the other tags, for clues about what happened.

But the key "e" is also the hotkey for opening the edit tag box. So if someone was already editing, and then they forgot... Apparently that happens rarely too. So if there's no obvious reasons for it, then this 'tag' can probably be removed, as an accidental typo.

However, if there is ever a legitimate purpose (like if there is ever an artist named this) then tagging that fact should be made a little more clear, like making the tag something like ee_(artist) instead.

Related tags:

• ee_(thekingangus) - a character
• eevee - a pokemon
• eee - an exclamation