Majin Tantei Nougami Neuro, Aitsu no Daihonmei Recommendations
These series are really different, but somehow, Aitsu no Daihonmei feels like the romance verision of Majin Tantei Nougami Neuro. MTNN is a dark (But comic) detective manga about the sadistic daemon Nougami Neuro who has come to earth to eat riddles, and forces high school student Katsuragi Yako to help him capture criminals. Aitsu is the story of the "Ugly" boy Yoshida, bullied by all girls in his class because the good looking and nice Saitou (Who is acctually quite sadistic) is allways using him as an excuse to not be with the girls who keeps asking him out.
Neuro and Saitou are both double