The handsome model couldn't resist giving his sweetheart a tender kiss as they sat down for dinner at the event, held at the New York Public Library.
Kylie - who this week put paid to rumours of trouble in her love life - was on bombshell form at the event, arriving in a raunchy gown by her designer pal Jean Paul Gaultier. The daring dress was slashed to the thigh - showing off her stockings and suspenders, and came complete with a leather glove and mini handcuffs.
The theme of the gala for amfAR - a foundation with supports innovative AIDS research programs – was black tie/black leather.
And Kylie adhered to this again with her second outfit of the night – a dress consisting of a white chiffon skirt and a black leather bust, sleaves and criss cross design.
She wore this to give an award to Latino singer Ricky Martin, who announced in March that he is gay. The dad of two was honoured for his charity work through his Ricky Martin foundation.
Kylie wasn't the only one with a job to do at the ceremony. Andres' moddelling skills were required – he walked the runway during a catwalk show featuring pieces from a roll call of designers.
Dolce & Gabanna, Tom Ford, Gaultier, Hugo Boss, Marc Jacobs, Karl Lagerfeld, Ralph Lauren and Jean Paul Gaultier were among the big names who showcased menswear designs.
And each donated a piece inspired by the black tie/black leather to be sold at auction to raise funds for amfAR.