Most likely
White Male,
Age 27-35
Criminal History would most likely include crimes, like theft, robbery, burglary (including fetish burglary), some violence like assault, possibly voyeurism.
Married, or living with someone at the time, significant other would most likely have suspicions, or even full blown knowledge about the individuals actions.
Most likely some form of unskilled labor if employed, could also be unemployed at the time of the killings.
Would've most likely been interviewed by the police.
Would follow the crimes, in the media
Some form of precipitating stress prior to the 1st attack
May've kept "trophies" from some or all his victims, most likely did.
Possibly suffered from some form of sexual dysfunction, id expect to see some form of simulated sexual assault possibly with masturbation following
Mother the dominant , and an overbearing figure in his life growing up
Like many displays both Psycho, and Sociopathic traits
Motive was sexual, (unlike Zodiac where power was the determining factor) .
Crimes most likely stopped because he was incarcerated for another crime, or he died.
If he was incarcerated though once released would most likely start in a similar fashion elsewhere, in terms of signature, though the MO would most likely change.
Not so sure the last crime attributed to the "Phantom" shooting up a house, was related though.