Sawajiri said, 'There is no question that it is mine'
Yuzuki Ishizawa, 20, was found collapsed and bleeding on the landing of a stairwell
Sawajiri, 33, allegedly possessed an unspecified amount of MDMA in Tokyo
Suspect told police, 'We got into a job-related dispute'
Suspect said upon his arrest in August, 'It was impossible for me to restrain myself'
Woman used a matchmaking app to solicit customers, police said
Victim was forced to drink extremely strong alcohol, police said
Suspect does 'not recall' the matter, police said
Body was bent at the head and wrapped in a towel, police said
Body of the woma had suffered about 15 stab wounds, police said