-----------UPDATE-----------
I've retrained v1.1 with the I2V model. Same dataset but the movement seems to be much improved. Use this version for I2V, stick with v1.0 if you use T2V. I've generated with some of the same images as v1.0 so you can see the difference.
-----------DETAILS-----------
This lora was trained on 25 videos for 184 epochs. The prompts I used are added to my samples, but it's fairly simple, such as:
A nude woman lying on a bed. She inserts two fingers into her *****. She masturbates by sliding her fingers in and out of her *****.
It should also work from a kneeling/all fours position but I've not tested this yet.
It also pairs quite well with my genitals helper lora (see suggested resources below), at a strength of 0.4-0.6. Help the vagina not get distorted so much as the fingers move in and out.