As far as I understand they just hang there under the slit. Pulling them in would be a biological flaw since, in the first place they are hanging outside because sperm can't survive in body temperature for long.
Internal/Exteranl testies & genital slit are two unrelated variables. Many changes that affect one affect the other, but you've obviously found one of the many exceptions to this trend.
As far as I understand they just hang there under the slit. Pulling them in would be a biological flaw since, in the first place they are hanging outside because sperm can't survive in body temperature for long.
Well that doesn't sound right if you consider that sperm live inside a woman for about three days in relative bliss if they make the ordeal through the biological gauntlet that is the vagina and cervix and cervical fluid is present. The real answer is that no one wants to take on the burden of making and then changing every scene to accommodate for internal testicles even though that could just be outsourced as bug/typo fixes, honestly.
No. "Genital Slit" is a status effect, not an appearance flag, so it can't be applied to individual penises. The closest to what you want would be the "Sheathed" flag.