I assume you tagged this yourself when you posted it.
Regarding pages 17–19, if the vagina is not evident, then this should be tagged "shemale" instead of "futanari". The "futa-" in "futanari" literally means "two" or "both", as in sets of genitals, just like "futari" (二人) means "two people" or "together". Despite what so many people seem to think, "futanari" is NOT an all-purpose synonym of "dickgirl".