Shirokuma's fondness for puns and wordplay may explain his brief hip-hop career as MC 469MA as hip-hop is all about rhyming and wordplay.
Panda is horrified that his little sister finds Handa (her 'prince') attractive. She points out that Handa's pandaesque physique accounts for that.
When Lion refers to himself as a hunter, Tiger and Wolf call him out saying his mother always fed him. Male lions do not hunt, and instead this role is given to the females.
Shirokuma replacing himself with Mama Red Squirrel during the baseball match, considering that the giraffes always caught his homerun attempts.
Grizzly's mother claiming she's only seventeen years old, and the other animals' surprise at her looks for her age which follows, is realistic if you think of a wild grizzly's lifespan.
Panda Mama: What? You don't look it at all! You're older than me? Grizzly's Mom: Well, I am a bear.
Panda's laziness and perpetual hunger make sense when you think that a bamboo diet is neither nutritious nor energetic and requires constant topping up. His mother is probably more energetic since she seems to have a more (realistically) varied diet...
Mandrill's the oni at setsubun because Grizzly's hibernating.
In a few episodes we see dozens of Pandas training with an older panda whom is called Grandpa Panda. This makes it easy to assume all the pandas are Panda's family, however it's never said how they're related to him, nor do we see them actually living there. It would make sense that Grandpa is a tai-chi master (who runs a school) and these Pandas are simply students (who may or may not be relatives regardless) who come from all over the city to train with him.
At the start of the show, Rin Rin's obsession with Panda is played up to the point of him seeming like a crazy stalker, who spends every moment thinking about pandas, culminating in him unintentionally leading on and then freaking out a high school girl until she ran away. Later in the show, Rin Rin's obsession is toned down a lot and he's shown to have a number of non-Panda related hobbies, even spending a night at Grizzly's Bar with the other characters. In between these two extremes is an episode where Full-Time Panda, feeling unappreciated, takes him out and comes onto him hard, much to his dismay. Even though it's never stated outright, it's likely that this awkward experience convinced Rin Rin that his behavior was unacceptable and that he needed to tone it down, which is why he's less obsessive in later episodes.
