The Late Late Show presenter was gushing about lady in red Aoibhinn Ni Shuilleabhain at the Mansion House party to celebrate the release of JFK In Ireland.
While the pair happily posed for photos together, they separately declined to be drawn on whether their romance is on, or off.
In fact both he and former Rose of Tralee Aoibhinn went out of their way to emphasise the point that they were out together "for the night" when asked individually about speculation surrounding their relationship.
"I have a date for the evening, Aoibhinn," Ryan told the Herald. "It's highly appropriate that she be here as she was part and parcel in some ways behind the scenes of how the book began and ended, so in many ways she's the muse and I'm glad she's here tonight, it's great."
Tubridy again declined to give a definitive answer when asked whether Aoibhinn was there in the capacity of his friend or girlfriend.
"She's my date for the evening and she's here tonight. That's all I'll say," he said.
Tubridy again paid tribute to the brunette beauty while making a speech on stage later in the evening, thanking her for her support and for being there on the night. "I'd like to thank Aoibhinn, she's here tonight here as well," he told the packed room. "She provided more patience than pretty much every hospital on this side of the Atlantic," he said.
"I'd like to thank her for being the woman who was not amused, but just a muse and I'd like to thank her for being here tonight obviously."
Dressed to impress in a fitted red dress and beige designer shoes, Aoibhinn was equally complimentary discussing Tubridy's latest accomplishment, but would not confirm whether they were back together.
Ryan's mum Catherine was also the recipient of some glowing praise from the Dublin-born broadcaster as he thanked those closest to him for their support.
"Mum feeds me stew when I'm hungry, she makes me eat soup when I don't want it. She even brings me medicine literally while I'm on air.
"She is the Rose Kennedy of my life and I'm very proud to have her here," he added.
Ryan also ravished praise on his father, four siblings, extended family members, friends, work colleagues and in particular his two young daughters Ella and Julia and urged those in attendance to give his late friend and colleague Gerry Ryan a round of applause.