부자연스러워요 · 부자연스러웠어요 · 부자연스러운 (+noun) (ㅂ irregular)
to be unnatural, awkward, forced
Example
사진 속 웃음이 좀 부자연스러워요.
The smile in the photo looks a bit forced.
Word parts
부 not+자 self+연 so, thus
부- 'not' + 자연스럽다 'natural'.
Good to know
In conversation 어색하다 is more common for awkward situations; 부자연스럽다 sounds more descriptive.