Merihim (whom Shana calls "Shiro") played a major role in training Shana prior to her contracting with Alastor and becoming a Flame Haze.
After making the contract, he challenges Shana to one final duel in which she wins. Shortly after, Tendōkyū (the floating landmass where Shana grew up and was trained) crumbles.
What is the fate of Merihim? Did Shana actually kill him? Did he die when Tendōkyū crumbles?
I wasn't able to figure this out after re-watching the episode (ep16) a few times.
MAL only lists him as "disappeared". But are there any sources that actually confirm his death?