That would work for me! If Sanae wasn't so powerful or so close behind him I'd be happy to watch Mart fight him from indoors, but when he can teleport and hide in shadows, walls won't really keep him out long enough for traps to be set. :c I know you'd rather keep him alive, so I think having him lose Sanae might work out best for us!

They can always get up to whatever shenanigans you want after the event -- Sanae's only trying to hurt him because he's forced to. When he's not in fighting mode, he's pretty chill.