It's just you.
There's nothing particularly powerfully explosive about starting fluid. It is just a combustible mix of stuff like ether and propane but the key is that vaporizes under just about any condition -- even extreme cold which is when it's typically used -- and it's easy to ignite. Even a weak spark on an engine cranking slowly will light the vapor under conditions when gasoline isn't atomizing nicely (e.g. it's -30oC) and the battery is dying...
It certainly won't hurt an engine unless there's a
ton of it in the intake manifold and the engine backfires...