Answer: Cimex sp.
This is a nice example of blood movement within the gut of a bedbug. Note the classic shape of this hard-to-eradicate pest.
The differential diagnosis in this case includes other Cimex species (e.g. bat bug); however, these can be ruled out by looking at the hairs on the pronotum. Unfortunately I didn't have a nice photo to show you a close up of the pronotum so the furthest you could go from just this movie is "Cimex sp."