Hello, inappropriate!

Lady Gaga kissed her married trumpeter Brian Newman during a performance at her Vegas Enigma residency last night and fans posted videos, questioning whether the act was "acting" or not.

Gaga split from fiance Christian Carino last month and of course her A Star Is Born co-star Bradley Cooper just split from his baby mama Irina Shayk last week. Is Gaga a home wrecker? Or just a very believable performer?