@murrayjames，

铁杆粉丝and 死忠粉 are very similar and interchangeable. 脑残粉 is a bit crazier which means a fan who will become crazy and act irrationally because of whatever or whichever celebrity (s)he is crazy about. Sometimes 脑残粉 would commit crime or hurt innocent people - 盲目地崇拜.