“something is fishy with him”
For me the adjective that comes to mind is ‘slick’.
That adjective has also been used on The Conservative Treehouse.
Now ‘slick’ can be good and ‘slick’ can be bad.
Hopefully, time will tell.
One other thought comes to mind, that of a sapling in a strong storm.
“the adjective that comes to mind is ‘slick’.”
Smarmy.