Also known as: ふた×女, ふたゆり, ふたなりレズセックス
A Futanari character and a female character engaged in sexual interactions.
This tag and Yuri are mutually exclusive. The only exceptions are if the post also contains yuri interactions, e.g. post #851759.
If you can't see the genitals of of the characters involved, use the rule of "fully female until proven otherwise," and consider the tag Implied Futanari instead.