[GAMEPLAY] Tahm Kench -W(Devour) is Disregarding/Ignoring the "Target Champions Only" Hotkey

Whenever I hold the "Target Champions Only" hotkey and press the W on a minion. Tahm Kench eats the minions anyways. This is very frustrating especially during a team fight, where I have accidental misplays and eat a minion.

1. Hold "Target Champions Only" hotkey which is "`" for me.
2. Press W(Devour) and Click on an enemy minion.
3. Tahm Kench eats it anyways.

I've been experimenting with this. The "Target Champions Only" works with Soraka, Taric, etc. It just doesn't work with Tahm Kench. Please fix. Thank you.