ltx2.3 - i2v 1.0
No audio , produces body horror sometimes. (and tail/sack?)
Works on it's own or merge at 0.8 + 0.4 with other nsfw loras for more motion/less body horror.

Works with strange kinks as well if prompted. (in reverse ?)

wan
Helps to avoid melting effect and helps inserting it into backdoor.
wan 2.2 test , trained on both realistic and animated clips about 60+40 %
Prompt format :
Anal insertion. The video depicts a man slowly inserting his dick into a woman's anus while she is lying on a couch

Use last frame only with no start frame for different effect.
Add other loras for more dynamic "transition".