He moved to Colorado in November 2011 with his girlfriend, Samantha Yowler, who is also from Ohio.
Samantha's brother Nick lives in Colorado.
On Friday, Matt, Samantha and Nick were in the movie theater when authorities say James Holmes opened fire - killing 12 people and injuring 58 others.
According to attorney Rob Scott, Matt and Nick dove on Samantha to shield her from the bullets. Samantha was shot in the knee, Nick was not injured.
Family and friends are remembering Sam and Matt as a loving young couple.
"He would bring her lunch all the time and sit there the whole time with her at lunch," Kellie Wall, who worked with Matt, said. "I think they were just really devoted to each other, and they had the sparkle of love in their eyes when they looked at each other."
Samantha had surgery for her injured knee and is recovering in the hospital.
McQuinn is from Butler Township in Montgomery County, Ohio. He was a graduate of Butler-Vandalia High School.
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