Camille Kostek won't be hard to spot in Mexico this weekend ... 'cause Rob Gronkowski's insanely attractive girlfriend is rockin' a neon yellow bikini ... and TMZ Sports has the pics!!
The NFL superstar and S.I. Swimsuit model are hangin' in Cabo San Lucas with friends Eric and Jessie James Decker ... and although it's only been a short time, there's already tons of heat.
Camille posted a pic of her bikini of choice -- it's highlighter yellow and brilliant --- and this time around, Gronk got his own matching trunks!