Conor McGregor's Sister Thongs Out ... (Gawk at Your Own Risk)

Conor McGregor isn't the only member of his family with a solid physique ...

The UFC superstar's sister, Aoife, is showing off her hot Irish bod on her honeymoon in the Maldives ... rockin' a tiny thong bikini bottom.

Aoife got married on New Year's Eve ... and Conor danced his face off at the reception.