The Leper Queen is a villain who opposed the X-Men when she was the leader of the Sapien League, a murderous anti-mutant group. The Leper Queen was a Christian, or at least a person of Christian background. Her precise denominational background is is unknown.
Below: The Leper Queen, the leader of the anti-mutant group the Sapien League, mourns her daughter Lucie Page, who was killed by mutants.
[Source: X-Men #180, published by Marvel Comics (2006), page 20; reprinted in X-Men: The Day After trade paperback (2006); written by Peter Milligan, pencilled by Roger Cruz, inked by Victor Olazaba with Don Hillsman III.
The inscription on the grave marker for the Leper Queen's daughter reads:
DIED AGED TWO
KILLED BY MUTANTS