Illustrious and its derivatives already know double vaginal as a concept, but the success rate through prompting alone is not very high (and also depends on the finetune). triple vaginal basically does not work on base Illustrious, or very rarely. This LoRA is meant to gently prod the model into the right direction, this is why it's only 9MB large.
Trigger: double vaginal
Trigger: triple vaginal
Supports multiple poses (refer to the example gallery for prompting). The following tags help with positions, but you can experiment yourself:
double penetration: A doggystyle pose
spread legs: A missionary-style pose
boy sandwich, standing sex, leg lift: A sandwich pose
The model may sometimes even do quadruple vaginal if the upper triggers are emphasized (e.g. (triple vaginal:1.2)), but the tag quadruple vaginal itself is basically without effect. Using explicit can improve the odds.