Jaime Alcaraz is very outgoing, always ready to try new things, and enjoys having fun. He has also shown himself to be very good at reading people, recognizing the potential in a Rickshaw-driver and a young cardfighter, which also makes him easy to get along with, so he makes friends very easily.
He is also considerably flirtatious, as shown in Turn 10 where he tries to confess his love towards a shrine maiden and Tokoha.
Being native from Spain, he frequently uses Spanish words when talking.
(Source: Cardfight!! Vanguard Wiki)