The Spanish Town Mardi Gras Parade is perhaps best-known for its biting sarcasm, lewd innuendo and endless homages to pink flamingoes.

But there’s an unusually earnest aspect to this year’s parade on Saturday. The parade’s king, Shelby Holmes, 38, was shot and killed more than a year ago in a perplexing case with no named motives or suspects.

And because Holmes donated several organs — one of which transformed the life of his friend — many of the parade floats will bear messages about organ donation.

The gesture might seem surprising for Baton Rouge’s largest Carnival parade, one at which phallic-sculpted ice pops make a regular appearance and whose theme soon after Katrina was “FEMAture Evacuation.”

But Holmes’ friend Doug Cossman, who received Holmes’ kidney through a transplant and has since been able to quit dialysis, says the parade’s message is a way to honor his memory while still having fun.

Duz Hamilton, captain of one of the oldest floats on the parade, agrees. Their float, “Krewe of Boyd Avenue” will feature Holmes’ picture as well as a logo for Crimestoppers, the anonymous crime tip hotline.

“We felt like because of Shelby’s death, because of what he did … this is something that our krewe wanted to do,” he said.

Holmes, a well-known Baton Rouge statistician and die-hard LSU fan, was walking home from his job as a ticket manager at the River Center when he was shot on Braddock Street in October 2013. He died shortly after at a hospital.

Police have not determined why someone would have wanted to kill him — police have said he was found with personal belongings nearby, making robbery an unlikely motive.

His death shook those who knew him. Friends said he never fought with anyone, and Cossman recounted his relentlessly upbeat energy.

“This is one of the finest people that I’ve ever had the pleasure of ... being able to call a friend,” Cossman said.

“Every time you saw Shelby, you were gonna have a better day.”

But while Cossman grieved over the loss of his friend for more than 20 years, he didn’t realize Holmes’ generosity as an organ donor would change his life.

Cossman’s 2½ years on dialysis ended shortly after he was told he was a candidate for one of Holmes’ kidneys, and he underwent surgery. Holmes’ mother, Dorothy Chissell, was able to pick him as a candidate for the transplant.

Cossman since has made a full recovery, and his days on dialysis are over.

Cossman said he is still shaken by Holmes’ loss. He still expects to see him at the River Center and at LSU baseball games.

“It’s still kind of mind-boggling that he’s gone and that we’re not gonna see him again,” Cossman said.

For Holmes’ mother, the pain of losing her son has not gotten any easier with time. She still avoids his room in her home, having only gone inside once since his death — and she takes a long route to the interstate so she won’t have to pass by the route he’d take while walking to work.

Chissell also still thinks about the last conversation she had with her son.

She drove him to work at the River Center in the morning, and he seemed unusually excited about an upcoming event. As he closed the car door he said, “All right” — their usual goodbye.

When Baton Rouge police arrived at her home to inform her of what happened, she was at first sure they were looking for someone else.

“It’s a total loss,” Chissell said. “There’s no way around it.”

Follow Daniel Bethencourt on Twitter, @_dbethencourt.