Ryoji can help with security. He volunteered with Tony Stark's special defense force, but considering that at least a handful of those people are going to be drafted, I'm presuming that the organization will fall apart a bit...
But yeah, Ryoji can take out the droids easy with electricity spells and is otherwise pretty powerful and durable, so please feel free to stick him wherever would be most appropriate (he's very amenable). He lacks Filial magic and he can be discreet because most of the time he looks like a teenage kid with an obnoxious scarf...
ETA: Ryoji can project around himself a barrier that at full power levels would 100% reflect everything thrown at it. Obviously it's diminished here, but if that affects where you want him...
Re: The Details
But yeah, Ryoji can take out the droids easy with electricity spells and is otherwise pretty powerful and durable, so please feel free to stick him wherever would be most appropriate (he's very amenable). He lacks Filial magic and he can be discreet because most of the time he looks like a teenage kid with an obnoxious scarf...
ETA: Ryoji can project around himself a barrier that at full power levels would 100% reflect everything thrown at it. Obviously it's diminished here, but if that affects where you want him...