Okay, here's the deal... I came up with this nick 5-6 years ago when I signed onto another anime-forum. I took the part Mang from manga and added ina... the ina-part was supposed to have something to do with anime but I can't remember the connection.
Today I changed my skype-name to mangina... it didn't take long until a friend of mine suddenly asked why I was called mangina. I explained why and got a reply back "do you know what a mangina is?" ... So, basically... after 5-6 years I got to know that the word actually exist and that it has a meaning (never heard of it before).