We’ve heard of dying over bullsh!t but this just makes no sense.

TYRIRK HARRIS and his girlfriend were well-known on their bustling Tacony block as lousy neighbors.

They hogged parking spaces. They took their time in silencing their frequently tripped car alarms. They let their two dogs run outside unleashed, biting and barking at passers-by and leaving piles of poo polka-dotting neighbors’ yards.

The couple’s hot temper was even more notorious.

Harris, 27, ended an argument over a snowy parking space last winter by placing his hand on his holstered gun, neighbors said. His girlfriend once posted a sign on her car, parked curbside, warning passers-by that she would shoot anyone who messed with it, neighbors said.

But Franklin Manuel Santana was new to the block. He, his wife, and their newborn daughter moved from Miami to their first-floor apartment on Torresdale Avenue near Magee just a month ago.

So when Santana knocked on Harris’ door late Tuesday afternoon to talk about the poo problem, he went unarmed – and unsuspecting.

Frances Fogarty, walking to the ShopRite to get T-bone steaks for Valentine’s Day dinner, witnessed what happened next.

“Frank was calm, polite,” Fogarty, 45, said yesterday. “He said: ‘I’m just asking you, please keep your dog off my lawn. If I have to come back here, there’s gonna be a problem.’

“Tyrirk said, ‘Oh, is that a threat?’ And then Tyrirk just pulled out the gun and shot him in the face. Then he stood over him and let out all the rest of the rounds, maybe nine or 10 more.”

Fogarty’s boyfriend had tackled her to the sidewalk out of the potential path of any stray bullets. But Fogarty couldn’t keep her eyes off the gunman. As Santana sagged lifelessly, Harris stalked around the porch for a few seconds.

“He looked around to see if anybody saw him, and then he went back upstairs. That’s what I call cold,” Fogarty said. Paramedics declared Santana, who would have turned 48 on Saturday, dead at 4:25 p.m. Harris, charged with murder and gun offenses, faces a preliminary hearing on Feb. 29.

In a city with countless tales of the murder of questionable motive, Santana’s slaying stunned even lifelong residents and seasoned cops.

“He lost his life overtaking pride in his lawn. A little girl is going to grow up without her daddy over this,” said neighbor Jessica Hill, who sat with Santana’s wife, Raquel, yesterday as she waited for her husband’s relatives to arrive from his native Yonkers, N.Y.

Raquel sobbed as she tried to make sense of something so senseless.

“You got to be careful. You can’t just speak to anybody anymore,” Raquel said, as 6-week-old Roxxanne slept in a car seat in the family’s cozy living room. “[Santana] had no weapons on him. [Harris] had no reason to shoot eight times.” But Harris’ history suggests he had a temper that was tough to tame.

Harris had a concealed-carry permit, but it was revoked last January, police said, declining to specify the reason.

His dogs – a Chihuahua and a German shepherd – were a constant bother to neighbors.

“They used to just have the Chihuahua,” said Jovetta Streets, who lives in the first-floor apartment under Harris. “But then they got another dog earlier this year, so then it was double-poop on everyone’s lawns.”

Yesterday, most lawns on either side of Harris’ apartment were studded with dog deposits.

Raquel said that she and her husband moved to Philadelphia “for a better life.” Santana worked in construction remodeling homes and had hoped to start a business with a friend here. That didn’t work out, but the couple decided to stay, and he was lining up other remodeling jobs, she said.

When Raquel heard the gun blasts Tuesday, she ran outside and spotted her husband collapsed near Harris’ porch. She sprinted to help but realized within seconds that his wounds were fatal. She called 9-1-1 on the cellphone she fished from her dead husband’s pocket.

When officers arrived and led Harris from his apartment in handcuffs, Raquel called out to him, as she crouched beside her husband’s body.

” ‘I can’t believe you did this! I can’t believe you did this to me and my family!’ ” she said she told him. “He just looked at me and didn’t say anything at all.”

We hope they put that trigger happy son of a b!tch on an express train to hell. SMH. That precious baby should not have to grow up without a father.

We should be able to knock on our neighbors’ doors without dying.