Flirty With Playmate Ana Cheri

Steph apparently wasn't the only Curry putting up shots on Tuesday night -- TMZ Sports is told the NBA superstar's dad was "respectfully flirty" with a former Playboy Playmate while sitting courtside at the Warriors vs. Knicks game.

Model Ana Cheri tells us her group of friends showed up to the historic game at Madison Square Garden together ... and by coincidence, they ended up sitting right next to Dell in the front row.

We're told the ex-NBAer couldn't have been nicer to Ana, Toria Ranae and Kirzlyn Gabriola throughout the night ... but was obviously giving a bit more attention to Miss October 2015.

Make no mistake -- Dell never crossed lines or made anyone feel uncomfortable, but Ana's…