This is one of my favorite names!
1) It doesn't sound like an awkward feminized form because you get see-RILL instead of SEER-ill.
2)
Cyril is such an ancient name with many well-known saints.
3) I always loved the name Marilla from
Anne of Green Gables and how
Anne shortened her daughter's name to "
Rilla".
4) It's so rare it doesn't even appear on the Beyond the Top 1000 SSA list.