Out of all the manifestations, Aizetsu was shown to be the calmest and most collected out of all five of them, as seen when instead of frivolously wasting time on entertainment as Urogi and Karaku or immediately getting agitated and enraged by anything like Sekido, Aizetsu was shown to calmly analyze his opponents and think out his strategy and figure out his opponents' abilities and weaknesses before attacking.
Oh, another demon slayer, what a pity, if only you wouldn't have found me. But there's no running from this so I have to do what I have to do.