I used him over 100 times in all the delves, but never he devour someone that i not target.
The english text says the same like german (often they say complete different things, so i look after this first).
Maybe complete wrong discription or is this a “streak” for me?
I’ve had a similar experience but only recently started using him. Ain’t he great in delves though? 
He is nice for all the immune guys. Either he devour or he curse for irongut.
A few people have reported the same thing. He is better this way tho
Why would you report a GOOD bug? 
Hopefully working as intended.