See, this just became a hostage situation, and Ohtori prolly thinks he's being smart. With a hostage, you have leverage, you can cut bits off and FedEx them to interested parties. You can demand concessions. And he will, because he thinks he can pull it off.

Or, and here's where I overthink things and they get weirdly complicated:

He lets one of his old students betray him. The guy's plotting gets discovered by Saionji, who takes him on as a potential ally - because the plotting has to be subtle enough that it escapes general notice, but Saionji has to spot it. Akio does his usual escaping act, they get the girl, yadda yadda, student redeemed.

And Akio now has a spy among the Duellists, ready to take them apart. And next time?

Next time he kills Annabelle. And he uses the old student as his pawn, because there's plenty more where that came from.

The message is clear. Trust no-one. I will find a way to strike at you. I will take from you that which gives you strength, and you will beg me to stop by the end.

Said it before, and I'll say it again. If you wanna fuck Clan Hutchins over, you gotta come at 'em sideways.

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"She's old, she's lame, she's barren too, // "She's not worth feed or hay, // "But I'll give her this," - he blew smoke at me - // "She was something in her day." -- Garnet Rogers, Small Victory

FiMFiction.net: we might accept blatant porn involving the cast of My Little Pony but as God is my witness we have standards.