(Cover) - EN Showbiz - Russell Brand's new squeeze is "completely in her comfort zone" with him.

The British star is currently romancing brunette beauty Isabella Brewster, whose older sister is actress Jordana Brewster.

Isabella has dated high-profile stars in the past - including Bradley Cooper - and sources close to her say she's totally secure with the attention she's receiving from her relationship with Russell.

"As well as dating famous men before, Isabella just recently left her job as a talent agent so she'll be completely in her comfort zone with Russell," a source told British newspaper The Sun.

"Although aside from the fame, her and Russell have a lot in common. They are both in recovery and totally into yoga. They are really enjoying spending time together."

Russell is officially single following his recent divorce from Katy Perry. The comedian-and-actor is famed for his charming ways and a source insists Isabella is fully aware of his womanising persona.

"Isabella knows Russell is a ladies' man so she is trying to play it cool," the insider added.

Russell's ex-wife Katy Perry is rumoured to be dating Florence + the Machine guitarist Rob Ackroyd. (C) Cover Media