The final battle takes place in the Hikariwo theater, where Takuru is trapped in a sightless and soundless prison in his own mind.  He'll need Onoe's help to break free, but after what he knows about her, can he bring himself to ask for it?
Anything less and I wouldn't 
have wanted to solve it, right?
لو كانَتْ أقلّ من ذلك لما رغبتُ في حلّها، صحيح؟
So ’nen halbherzigen Fall
hätte ich auch nicht lösen wollen.
Y no hubiera querido resolverlos
de lo contrario.
Y no habría querido resolverlos
de lo contrario.
Je ne me serais pas intéressé
à des affaires quelconques.
Non avrei avuto voglia di risolvere
 un caso architettato male.
Qualquer coisa menor e eu não
 iria querer resolvê-lo, não é?