USDJPY is in a wave 'c' down of the ABC decline that is correcting the rally from 2011-2015.
Wave 'c' is the post-triangle thrust from wave 'b'. It has completed waves 1, 2, and 3 and is now nearing the end of wave 4. If wave 4 is a triangle, based on its present parameters it appears to be targeting down to at least near the 106 level for the 5th wave.
The 106 level also happens to correspond to the .382 retracement of the rally from 2011-2015.
At this stage in its development, Wave 4 should not rise above 116.776, which is the extreme of wave 1. That would be the nearest reasonable stop loss level for a short from here, based on the Elliott Wave rule for a 4th wave not ending in the territory of the corresponding 1st wave.