i want to name my character shinobu oshino but am not allowed

[Saccharin]

A lot of copyrighted named are blacklisted like EveK said. You actually can't even make FC ranks with certain FF names.

There is a Shinobu Oshino on Diabolos. She's a level 2, Lala Pugilist. :B
~*RESEARCH*~

The above was probably created before the name was added to a list. Most game companies usually only force a rename if someone has reported it.