The dramatic changes Christina Grimmie's killer made in a bid to impress her

Colleagues of the murderer of US pop singer Christina Grimmie have detailed the dramatic lengths he took in an attempt to woo the entertainer.

Kevin Loibl, 27, shot Ms Grimmie three times as her arms were outstretched to hug him at a fan meet-and-greet following a performance in Orlando, Florida, on Saturday. He then turned the gun on himself.

Former co-workers of Loibl's at a Florida Best Buy store have revealed to TMZ the lengths he had been going to change his appearance to what he believed Grimmie would find attractive.

Loibl had undergone Lasik eye surgery and hair transplants in the months leading up to the shooting. He also reportedly became a vegan, in a bid to lose weight.

The former member of Best Buy's Geek Squad tech support team hinted to colleagues that he met Ms Grimmie after a concert in March and had played online games with her. Both claims have been denied by Ms Grimmie's representatives.

Co-workers say Loibl became enraged when photographs of Grimmie with another man - her record producer and the man believed to be her boyfriend, Stephen Rezza - would appear on social media.

Mr Rezza has since changed the tagline of his Instagram profile to: "Carrying out the rest of my life in honour of Christina's legacy #RIPCHRISTINAGRIMMIE"

Loibl's family have not spoken with the media, beyond a note they had sticky-taped to their front door, which read: "Deepest sorrow for lost [sic] to the family, friends and fans of the very talented, loving Christina Grimmie. No other comments."

Grimmie first found fame as a YouTube performer before finishing in third place on the 2014 season of The Voice.

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