Total Recommendations: 5
Both sing to fight the enemy. The difference is that mermaid melody is more childish that senki.
Some female characters from Nyan Koi are similar of the female characters of Love hina. Both are harem, are comedy and some ecchi parts
Well... both series are similar becouse the ambient: The society doesnt accept that "rich" peaople and "poor" get in love, for example.
well, Same authors and apper of some characters of the move and if you pay atention you will see in the end of x/1999 the beginning of tokyo revelations. this is for Tokyo in ruins.