| Significant |
|Alexis Castle (ex-girlfriend)|
|Appearances||Pi - List of Appearances|
|Portrayed by||Myko Olivier|
Pi is a recurring character in the sixth season of Castle. Last (and legal) name unknown.
He was the boyfriend of Alexis Castle, whom she met while in Costa Rica, and then brought him back home to New York. He calls Castle "Mr. C" and it has been seen that he is messy and doesn't clean up after himself, much to Castle's dismay.
Pi and Alexis later move into an apartment together that, due to lack of money, is rather improvised. During an inspection of the apartment by Castle and Martha, it is revealed that his job is to "determine the strength of the hive," or in other words, he counts bees.
Castle was disapproving of him since their first meeting, but became more receptive to the idea near the end of "Like Father, Like Daughter". He was last seen in "Limelight", and last heard about when Alexis broke up with him and moved back home at the end of "Room 147".