Head of college in university repeatedly found in pubs? That’s not suspicious (9)

I believe the answer is:

innocuous

I'm a little stuck... Click here to teach me more about this clue!

But I can't explain it at all! Could you help me understand?

(Other definitions for innocuous that I've seen before include "Harmless" , "Not harmful or offensive" .)

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app