First take a full database backup.
Users often may make a u-turn and may want you to restore the DB Image may be NSFW.
Clik here to view.
use ANDREAS_20150511
go
drop all users/aliases except 'dbo'
(you can use various techniques !!)
use master
go
select * from monProcess where DBName = 'ANDREAS_20150511'
go
kill the SPIDs reported by above
Also
select * from monLocks where DBName = 'ANDREAS_20150511'
go
kill the SPIDs reported by above
Repeat both until you get no SPIDs
Now you should be able to drop the database Image may be NSFW.
Clik here to view.
HTH
Good luck
Avinash