0:17 - 0:20 is Niregi based on handwriting in the Gengashuu, he probably goes to the end of the clip as he does the phone call between Dazai and Odasaku just after this - probably did at least 15s - end imo

The beginning is either still Niregi or part of Hiroe's scene (he's confirmed for Odasaku sitting down and looking up just before this)