Animate bug chewing on leaf

I would like to know if anyone has any ideas on how to animate the formation of a hole in a leaf when a bug, say a caterpillar, chews on the leaf. So, first making a hole, then chewing along the way caterpillars do. I’ve tried using shape keys, but it always looks sort of like a Star Trek door opening, like the bug itself is not doing it, but just standing there and “Voila!”, a hole forms in the leaf.

Thanks in advance for your help!

Thanks for the tip Blenderallday! Sorry I didn’t respond earlier. I ended up using an explode modifier, which wasn’t a great solution but worked for that particular project, but I might try your brush/transparency mask idea on my current project…it seems like it would make the eating more realistic.