Like the title suggests, I would hope that a “dickgirl on female" tag can be added where we have at least one, or many, Futanari showing any instances of sexual/nonsexual interaction with a normal female girl.

For Futanari manga, I noticed the manga section has a "male on dickgirl" tag and a "dickgirl on dickgirl" tag. Having a "dickgirl on female" tag can make things easier when looking for manga similar to these two examples.
http://ehentaihip.com/g/1111267/31c4c8fc06/
http://ehentaihip.com/g/1102761/f17643b6e6/

I am aware that there is a “sole dickgirl” tag. However, as mentioned earlier, I feel that a “dickgirl on female" tag would help broaden the search where there can be more than one Futanari girl on only one girl. A “sole dickgirl” wouldn’t be enough to pinpoint the search since a “sole dickgirl” tag can lead to other unwanted results such as a Futanari girl with a guy or a Futanari girl solely by herself.

Thank you to anyone who reads and agrees with this.