Angel Loyer-Lawrence headed out with a girlfriend last Friday to hang out at a local park. But the B.C. teen ended the night dead in her boyfriend's lap, after taking what she thought was MDMA.

The 16-year-old and her friend bought the pills from a street dealer, believing they were the drug commonly called ecstasy, police said.

But as they walked from Moody Park in New Westminster, B.C., things went very wrong. The girls' eyes started to move rapidly, and they called for help to a passerby.

"It's really sad. I think we are all feeling pretty devastated. It's crazy to think how fast a person's life can go from living to not living. How fast the light can dwindle is scary," said Kris Coles, who had stopped to help.

Loyer-Lawrence collapsed in the 1300 block of Hamilton Street, soon after leaving Moody Park. Friends called 911. (Christer Waara/CBC)

Friends had emerged from the park with the two teens, clearly in trouble, before Loyer-Lawrence collapsed.

"[She] was walking and her boyfriend … kind of laid her down right there and put her head on his lap, and she started to have a seizure and lock up, and then she passed," said Coles.

"I heard that they thought that they were taking molly, but I didn't know it would end up this bad."

Loyer-Lawrence's friend was taken to hospital and survived; she returned to school the following week, Coles said.

A GoFundMe page has been set up to pay for Loyer-Lawrence's funeral. On it, she is described as a 'funny wild spirit that was known for her beauty.' (GoFundMe)

"As soon as I saw her [friend], my eyes started to tear up. It was good to see her alive and not in the terrified state that she was," Coles said.

Coles did not know Loyer-Lawrence well but, at school, was struck by her spirit.

"Anytime I saw her, she was always happy. She always held herself up high and never let anyone bring her down. It's sad to lose a soul such as hers."

A fundraising page for Loyer-Lawrence's funeral described the teen as a ''funny, wild spirit known for her beauty."

Relatives said she was living with her sister in Vancouver and attending Power Alternate Secondary School, a small 60-student school in New Westminster.

Loyer-Lawrence often wrote about missing her mother, Patricia Emily Loyer, posting images of a grave marker and many messages of love to her. (Angel Loyer-Lawrence/Facebook)

On social media, the teen mourned the loss of her own mother in an open letter posted in late 2016.

"I know you're watching over me, mom. And wondering what am I doing to myself and probably why. I've been going to the wrong path and doing choices I'd never make if you were alive. I've been thinking about you, mom, and I always wondered what would you be like and how would your voice sound and how your hugs felt and knowing that I have a mother that would be there for me."

"Hate feeling like this. I just need my mom," she wrote in January of her mother's death.

She also described how losing her mom made her feel "broken."

Police said the pills she took may have been tainted with fentanyl, but toxicology reports are not expected until the end of the week.

In the wake of Loyer-Lawrence's death, Coles hopes others are careful.

"Everybody thinks, 'Oh that will never happen to me' — until it does."