先輩は、嫌味なくらいの完璧超人でしたからね。だから逆にその「癖」は先輩の可愛げ・・・というか、チャームポイントでしたよ。 You were always a perfect 'superhuman' to an infuriating extent, and so that 'habit' was actually one of your cute, or rather charming, attributes.
Ubermensch (e.g. Nietzsche's ideal man of the future); overman