A source tells ET that Tyler, who wore jeans and a maroon shirt to the bash, and Gigi "are very much together" and have "just started getting serious."
"Things are going very well," the source says. "Tyler joined Gigi at the Republic Records VMA after-party, and it was clear they were a couple."
"Things are very easy for Tyler and Gigi," the source adds of the pair, who were also joined by Jesse Tyler Ferguson and Justin Mikita at the party. "They both are extremely kind and want the same things in life. They both are in the modeling world and understand each other’s passion."