If you are a Christian and you are casting spells you are in danger of going to hell.
God forbids anyone using the devils powers to cast spells or even to practice witchcraft. If you think it does not matter you are in for a big surprise. demons will curse you and your family.
Bible says this about this practice.
Deut. 18:10-12
10There shall not be found among you any one that maketh his son or his daughter to pass through the fire, or that useth divination, or an observer of times, or an enchanter, or a witch.
11Or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer.
12For all that do these things are an abomination unto the LORD: and because of these abominations the LORD thy God doth drive them out from before thee.
If you are a Christian do not use black magic but instead ask the Lord to bring the missing person to you.
My friends daughters cat was once lost and did not even have a collar on and we asked the Lord to bring that cat back and the girl and this mother went looking for the cat and 4 days went by and after that a person in the building where the girl was had asked all tenants if someone had lost a cat. My friends daughter's cat was found and returned to her and the cat had never been out on the street ever. It was a indoor persian cat that could have been stolen and taken some place else but God took care of the cat till it was revealed as to where it was.
I would never ask the devil to do anything, Because I am a Christian and I know what happens when you are cursed. Only Jesus can set you free. But you must repent. I am sure the Harry Potter books gave you the idea that black magic is for play and fun.
NOT