No, Hello Kitty is not bad. Hello Kitty is a popular children's cartoon, clothing line and accessory line, for little girls. There have been some misconceptions behind the brand as some have fallen victim to believing Urban Legends. You can read about Hello Kitty, and how Hello Kitty came about at http://www.ask.com/wiki/Hello_Kitty.
Its not just about urban legends. Through fasting and prayer, the Lord Jesus has revealed to me that this company is in the hands of the devil and has many in bondage from the freedom of Christ. I would recommend being discrete about this and if possible dispose of all Hello Kitty merchandise.