Pandora Hearts, Yumekui Merry Recommendations
While there are some parallels between the plot lines and characters, the most striking similarity between these two shows is in the atmosphere. There is good comradery between the the characters and a gentle kindness that eminates from the protagonist of both shows. However, despite that there is a nagging creepiness which hangs in the background and a sense that all is not quite as it may first appear. The definitions of good and evil, write and wrong, seem to become complicated an lost in the varied perspectives of the characters.
Similar in art styles and fantasy concepts as well as the 'normal boy, mysterious girl' concepts. Same charming animation and plot.
The setting and characters are similar
both anime have a similar feel
Merry and Alice are both unsure of their past and from another world.
The anime have a similar feel (though yumekui merry has less humour)
both have another world
In both Yumekui Merry and Pandora Hearts, the male lead who is fairly useless in combat makes a contract with a strong and amnesia-stricken tsundere female lead, and both shows have a surreal, dreamlike atmosphere.
They both are very fantasy related with an alternate world and creatures other than humans. They have very similar male main character, Oz is similar to Yumeji
PH: The Abyss and creatures called Chains
YM: The Dream World and Dream Demons
Both main female characters lost their memories. Both animes have another world that have powerful creatures. Ironically, both female characters are ridiculously strong in my opinion.