Turn your favorite person into a chonk. Or create a new chonk hero. The trigger is mugquake and seems to be mandatory to get a good result. Use it at a strength of around 0.80 for good results, or push it to 1.0 for more severe.

You may find it helps to add a description like, "They have a chubby silhouette, broad cheeks, a huge head, and a chubby double chin."

This LoRA really wants to fill the frame, so landscape orientation works best.