Romance

Romance is a running gag on The Petri Dish because Thaddeus Euphemism, iBall, and to a lesser extent Bob, are unlucky in love.

Appearances
At the end of the Exploding dog arc, the exploding dog tries to mate with the guard dog at the factory next door to the Clones 'R' Us building, but explodes.

In Irene's debut, some of Bob's "lower functions" begin to surface, including sexuality. When Andrew Wong found out that Bob was bored and lonely, Thaddeus tried to make him a girlfriend, Irene, but when they dated virtually, she dumped him and left.

The Squirrels' law arc reveals that Thaddeus is divorced and that his ex-wife had an aggressive lawyer.

In the GPS arc, Bob romanced a sentient GPS, then Siri.

In the Pink-eye arc, iBall is disappointed at not making it with the ladies, but Bob points out that he doesn't have very good odds of succeeding at dating them with one huge eye and Atticus following him around doing expressions for him.

In the Irene comes back arc, Bob and Irene start dating again. They have trouble at first, but eventually things smooth out.

In Gwog's return, it's revealed that Gwog is married to Wibbley.

In one strip, Thaddeus describes himself as a "chick magnet" but the kind of magnet that repels.

In the Kang romance arc, Thaddeus dated Nicole, who was symbiotically bonded with a monster named Kang.

In the Thaddeus seeks a girlfriend arc, Thaddeus went looking for a woman to date, eventually settling on Marcie.

Soon afterwards, Thaddeus and a bacterium exchanged flirtatious looks.