PHILADELPHIA -- There are dozens of shop cats in Philadelphia, but only one employed feline has had a Latin Grammy-nominated pianist compose a tango in its honor.

The cat muse in question is Sheldon, the live-in kitty who greets patrons and occasionally corrects dance technique at the Philadelphia Argentine Tango School in the Fishtown neighborhood. He came to reside in the studio — and its attached apartment — by way of the school’s director Meredith Klein, who rescued Sheldon from Palmer Park in 2017.

Since then, he’s spent the past six years capturing the hearts of guest Argentine tango instructors, novice dancers, and performers — including New York City-based tango pianist and composer Emiliano Messiez.

Messiez composed the three-part tango “Sheldoneando” as the opening track for the June 2023 album Psicoporteño, which was coproduced by Klein. It is the first release from Típicia Messiez, the 10-member traditional tango orchestra Klein helped Messiez create at the 2019 Philadelphia Tango Festival.

The song’s title translates to “Sheldon-ing,” or the act of being Sheldon the cat. To Klein, Sheldon-ing includes jumping into strangers’ laps, finding new positions for snuggles, and secretly craving life back on the streets.

“Sheldoneando” is about “having the life of dreams — living in a tango studio, having admirers — yet yearning to escape to have adventures,” Klein said.

Klein said Sheldon (whose true age is unknown) was a former outdoor cat who ended up in Palmer Park after his owners abandoned him and moved away. When Klein attempted to domesticate him in 2017, she said he escaped after three days. He was tracked down by a group of Fishtown residents who used to feed him dinner.

“He used to have a set schedule to canvass the neighborhood for food,” said Klein. “He’d stop by one house at 5 p.m. to get his first dinner, and then another at 9 p.m. to get his second dinner, and then another at 2 a.m. to get his third dinner, and so on. He’s very smart.”

Now, Sheldon’s chief pastimes include lounging in the studio’s front window, demanding pets at the registration table, and “sashaying” across the dance floor as if he’s “commenting on people’s forms,” Klein said.

Founded in 2008 as a hub for Argentine tango music, dance, and poetry, Klein uses the Philadelphia Argentine Tango School to host guest artists and help them get visas, often offering them the studio’s attached apartment for their stay. Sheldon, of course, comes with the territory.

“Our teachers not only have to be extraordinary tango performers, they also have to like Sheldon,” Klein said. “Cuddling him is part of their job.”

Messiez, who is from Buenos Aires, met Sheldon and Klein in 2017 when he stepped in as a fill-in pianist for an event the tango school was hosting at the Barnes Foundation. Since then, Messiez has gone on to perform internationally, compose for several Broadway and regional musicals, and collaborate on more than 90 Philadelphia Tango School events with Klein, Sheldon often lounging at the foot of the studio’s piano while Messiez plays.

“We always joked that Sheldon deserved a song,” said Messiez, who recently received his first Latin Grammy nomination in the best tango album category for his 2022 album Ahora.

Messiez said “Sheldoneando” came together in about a week. After writing the melody from bed one morning in 10 minutes, Messiez began researching sounds that cats enjoy.

“I’m writing a song for a cat, so I asked myself, ‘What do I do to be fair?’” Messiez said.

The composer ended up learning that although cats can hear noises at higher frequencies than humans, they actually enjoy lower register sounds — hence the slow, almost ominous-sounding beginning to “Sheldoneando.”

“When you hear the song you can see Sheldon stalking across the studio,” said Klein. Messiez said he imagines Sheldon happily watching couples dance every time he plays it.

As for Sheldon, he seems to like the song, even if he has no idea it was composed for him. Klein says she occasionally plays “Sheldoneando” to summon him out from hiding.

“Sheldon’s not humble,” said Klein. “He just doesn’t know anything about music or composition.”