undertail
Term used in place of Undertale when the content in question is NSFW. Toby Fox, the developer of Undertale, invented the term in order to make it easy to distinguish between SFW and NSFW Undertale content. Most frequently used as a tag for Rule 34 of Undertale.
The Urban Dictionary Mug

Loved this mug! So unique and you can edit the text to add something unique.
I gave it to my friend who took money from me and never returned.
I love the fact that I was able to customize my name since I've never been able to find anything with my name. The only downside is it's smaller than I thought it would be (I guess I didn't pay much attention to that), wish it was bigger, only about 10 oz total.
It's simply awesome; and plus, the word means a lot.
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