Kanye West Performs in Atlantic City, Serenades Kim Kardashian

Kanye West put on his first solo concert in over a year Friday night in Atlantic City, but the rapper wasn't really alone.

He made multiple references throughout the night to Kim Kardashian, who watched the festivities from a private box alongside close friend Jonathan Cheban.

Kanye West - "Way Too Cold" (Live in Atlantic City)

At one point, Kanye broke out into a rendition of "Way Too Cold" (aka "Theraflu"), the track in which he initially declared his love for Kim. At another, he told attendees: "If you love someone tonight… hold on real tight!"

Kardashian, witnesses tells Us Weekly, jokingly hugged herself in response.

Kanye and Kim are reportedly heating up. Big time. A recent story claimed he's seriously thinking of putting a ring on Kardashian's finger, despite the fact that she is legally still married and despite the fact that the relationship is clearly just for PR purposes.