Russell Wilson has 2 kids with Ciara, but #3 could be on the way soon ... 'cause the NFL star was LOVING his wife's topless twerk sesh on Instagram, letting the whole world know just how much he was feeling it.
The 36-year-old singer posted the steamy vid to her 30 million followers on Thursday ... dropping low and putting her dance skills on display while balancing a bottle of booze on her head, as part of the "Balance Challenge" trend.
"She Got Balance," Ciara captioned the vid. "That @TenToOneRum is fun! ud83eudd29"
The clip is obviously great, but what had even more people going "OMG" was the Seattle Seahawks QB's reaction to the vid.