This was an interesting episode, to say the least.
I like Kyoko's frequent attempts to kiss Train, and his equally frequent avoidance technique. And his reaction to her spicy chocolates was funny too.
But it was the concept of a transformation-causing bullet that really got my attention, not to mention the fact that Train was the one who was injected with it, and as a result, was turned into a child-like version of himself, which I certainly didn't expect.
(Personally though, I was kinda thinking that Train would turn into something like, oh, say, a cat-like monster, but that's just me.)
However, the turn-out was still very interesting. I eagerly await the next episode, as well as Train's reaction to his "situation". Poor Train...