 If you liked
Kami nomi zo Shiru Sekai
|
 ...then you might like
Beelzebub
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Both have the protagonist that forced to be responsible to devil.
at first the story was to be get out from involved with devil ( kaminomi was getting girls, Beelzebub was search for someone strong ! )
then the story became more interesting. and both have a girl to support the protagonist.