The 31-year-old 'Glee' actor confirmed his relationship with the 19-year-old actress and is looking forward to ''making magic'' with the starlet.
He told Us Weekly magazine: ''Denyse is talented and beautiful on the inside and out.
''I look forward to getting to know her more and making magic.''
Friends say the relationship is still in the early stages, with a source revealing they were introduced by Denyse's producer and bonded over one another's music.
The insider added that ''they are hitting it off''.
News of Mark's new relationship comes just after it was revealed his former girlfriend, and 'Glee' co-star Naya Rivera, married actor Ryan Dorsey following a whirlwind romance.
Although the 27-year-old actress only split from rapper fiance Big Sean in April, she and longtime friend Ryan tied the knot on July 19 in Cabo San Lucas, Mexico.
They said: ''We feel truly blessed to be joined as husband and wife. Our special day was fated and everything we could have ever asked for.
''True love always prevails.''
The wedding came as even more of a shock as it was only revealed last week that the couple were dating, when they were spotted on vacation together in Mexico.
However, they have been friends for four years after meeting when Ryan moved to Los Angeles.