The paratrooper who celebrated his upcoming departure from the Army by jumping with his pet Siamese fighting fish — and whose selfie of the act later went viral on social media — will serve 12 days of extra duty before closing out his time in uniform.

Spc. Matthew Tattersall, who is assigned to 2nd Battalion, 505th Infantry Regiment, 3rd Brigade Combat Team, 82nd Airborne Division, received a company-grade Article 15, with the extra duty as punishment.

"The way I see it, if you do the crime, you'd better be willing to do the time," Tattersall said. "They certainly, if they absolutely wanted to, the punishment could have been far worse, so I'm not upset about anything. I understand that there were going to be consequences for it."

Tattersall, who had already written a 1,000-word essay about the importance of airborne safety and professionalism in the Army, also could be bumped down to E-3 if he breaks any more Army regulations.

"If I make one mistake, they take my rank," he said. "They tossed me a bone when it comes to not taking my rank."

When handing him his punishment Tuesday, Tattersall said his battalion commander explained that his actions were unsafe.

"It wasn't a laughing matter," Tattersall said. "And the essay I wrote, I didn't take the essay very seriously, which I should have."

Tattersall, an infantryman with a deployment to Afghanistan, joined the Army in 2011, shipping to basic training in January 2012. He will complete his enlistment on May 20.

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To mark his last jump April 11, Tattersall decided to bring his fish, "Willy MakeIt", along for the ride.

"It was a daytime combat jump, but with me being so close to getting out, I didn't have any gear, so it was a Hollywood jump for me," Tattersall said shortly after the jump.

Tattersall's fish, "Willie Did MakeIt," survived his first jump. It will probably be the fish's last.

Photo Credit: Spc. Matthew Tattersall

He and his friends had long talked about doing something special or unique for their last jump, but "no one actually went through with it," he said at the time.

So when his turn came, "I wanted to make it awesome, and I did just that," he said.

On the day of the jump, no one knew what Tattersall was planning, he said.

As he jumped from the C-17 and fell to the ground under the canopy of his parachute, Tattersall took a quick selfie.

He was careful to make sure no other jumpers were nearby, he said.

Tattersall and Willy MakeIt made it safely to the ground, and the hardy fish earned a middle name. He's now Willy Did MakeIt.

Tattersall, who will spend his evenings and weekends through May 9 doing everything from cleaning hallways to moving boxes, said he is relieved that he will be able to transition out of the Army as scheduled.

Tattersall is expected to start his transition leave on May 20, and he has a job lined up to begin May 28.

"I'm just relieved I'll be able to go home on the 21st," he said. "That's really all I was worried about in the first place."

He also wishes Willy had been punished as well.

"He thinks that this is the funniest thing in the world, and it's not," Tattersall said.