Neon Genesis Evangelion (1995) : 1x9

Asuka joins Shinji’s class at school, and moves in with Misato and him in their apartment. As Asuka adjusts to Japan (or rather, everyone else adapts to her...), a new Angel attacks which is capable of splitting itself into two identical copies. EVA-01 and EVA-02 are defeated, and NERV is publicly humiliated. With the Angel in a week-long regeneration period after an N² Mine attack by the JSSDF, Asuka and Shinji must learn to "synchronize" with each others movements combat, in order to defeat it once and for all.