well i can think of two things that might explain this:

1: you are not a sysadmin, and the object in question is outside of your permissions scope. ie the sysadmin created a table/procedure/function/view named "HighCharacter", so it exists, but you cannot see it due to permissions. this is most likely true, since your LIKE statement on sys.objects did not return the object in question.

2. a little tunnel vision possibility: you want to create a FUNCTION named "HighCharacter", but a Table,View or Procedure already exists by that name.

DROP FUNCTION would fail, becuase it should be DROP PROCEDURE, maybe.

select

schema_name(schema_id) As SchemaName,

name As ObjectName,

type_desc as ObjectType

from sys.objects where name = 'HighCharacter'

Create your Function with a different name, like as HighCharacterV2 and i bet it works just fine.