This is literally the point of view of a monster, so yay for angsizing.
The guy is 109 px, which I'll assume is 160 cm (MC is pretty short despite being 18)
The view is 515 px
2atan(tan(70deg/2)*[109/515] = 16.859669810982 degrees
539.81 cm, or 5.3981 meters.
The dude literally states he is moving too fast for him to see (which is why he put a wire in the way, but that's besides the point), so I'll assume he has the reaction speed of a normal person, 13 ms (he is turning into a monster, which boosts him beyond humanly possibly)
5.3981/0.08 is 67.47625 m/s so Subsonic