reluctantly; against one's will; despite oneself
Used when someone does something they would rather not do, often out of obligation or necessity. Conveys a sense of unwillingness or lack of enthusiasm.
Reluctantly, I accepted the proposal.
Against his will, he was ordered to transfer.
From 不本意 (unwilling, reluctant) + ながら (while, although). The combination forms a set adverbial phrase meaning 'although unwillingly' or 'reluctantly'.