AI is really only cost-effective for stills and placeholder art. I make a little over $60 per hour in my current position, meanwhile I could go and pay an artist on fiver $10-$20 to animate a still and save myself the trouble. Because remember, my work is worth $60+ an hour, meaning if I hire an artist who would save me 3 or 4 hours worth of work I've effectively saved upwards of $160-220 in time costs.
If you're still invested in learning to do it yourself? Civitai has plenty of workflows and models that when combined can get pretty good results. I think img2vid is what you're actually looking for. Though, you'll most likely need Lora's/Workflow's for each sexual act.