You may have to use specific Lora that are trained for anal sex between men.
I tend to search for “gay” on Civitai and that’s a good starting place. If anyone knows any good ones, please share links.
I had a handful I used when I was doing SD1.5. Since switching to SDXL and Pony based male checkpoints, I’ve had a lot less issues.
Which checkpoint are you starting with?
I use different checkpoints and test which one gives a more interesting or better result.
I have CyberPony, AlbedoBaseXL, CyberRealisticXL, LustifySDXL, PhotonicFusionSDXL, and Photorealistic_AllPurpose. I also use LoRAs.
Here’s an example of one of my prompts:
score_9, score_8_up, score_8_up,raw, realisitc, photo, ((gay, yaoi))1guy, 1man, a slutty guy in lap, ((nsfw)) sexy 20yo twink guy, submissive,perfect round ass, squeezing ass, ass up, sweaty skin, shiny skin,thick thighs, 1man, big veiny erect cock, anal, anal penetration, сreampie, cum, volumetric lighting, car interior, detailed car interior, glowing, neon, cinematic photo, professional postprocessing. remarkable color, ultra realistic, textured skin, remarkable detailed pupils, realistic dull skin noise, visible skin detail, skin fuzz, dry skin, shot with cinematic camera,highly detailed <lora:casting shadow style v3:1> <lora:Gay_anal_sex:1> <lora:Cum_BigLust_03:1>
And here’s what I’m getting: