On one occasion, Riko is moved to tears by something Reg says and proceeds to hug him while crying. When they separate, we see that it has left a snot trail from her nose to Reg's hair.
When the two meet Ozen for the first time, Riko thanks her profusely for letting them stay at the camp, and does so by bowing really fast... right into the table she's sitting at.
Later when Ozen reveals more of her past with Lyza, mentioning about taking care of Riko, Riko is so overjoyed she goes to hug her, only to receive a Finger Poke of Doom right to the forehead.
In a flashback to Ozen's past, one of the events recounted is Lyza revealing her marriage to her. Ozen's response is a comical Ghostly Gape, in stark contrast to the usual creepy expressions.
Nanachi gives Reg a list of items that they need to cure Riko's poisoned status from Orby. It is urgent and has a strict and literal deadline, and we are treated to Reg's serious fetch quest. Then it turns out Nanachi only needed one of those items to cure Riko. The rest was dinner. Nanachi had Reg running errands. What makes this even better is how Nanachi responds to Reg's indignation. They can't go foraging while treating Riko and they can't treat Riko if weak from hunger, which makes Reg apologize again.
Nanachi (thinking): He really is a pushover.
Reg attempted to cook for himself and Nanachi. The problem is, he also has no idea how to cook. As the result, his attempt turns out even worse than Nanachi's, which is made funnier by Nanachi's blatant admission that the food is even worse, and their playful mocking of Reg if he dare say their food is irredeemable. Reg shamefully admits it, while trying to swallow the food in disgust.
Near the end of the first season, Nanachi invites Riko and Reg to have a bath in one of the safe waters outside their hut. This not being a time for social norms, they're both naked, although we don't see anything below mid-torso, and with them being twelve years old, there's nothing for the audience to stare at. Reg unknowingly likes what he sees, apparently, as Riko notices just how much like a real boy he is — her shocked reaction says it all:
Riko: "W-W-What's going on with your penis?!"
In the manga, there is actually a running gag about Reg's Rod. Such anecdotes include: Whenever Reg finds something extremely fluffy (Nanachi is on the end of this one, and then it happens AGAIN with Faputa), and a whole scene between Riko and Prushka happens in Idolfront simply because Prushka doesn't actually know what Riko is talking about until we get this line and Riko's priceless reaction◊ to it:
Prushka: Oh! You mean like Papa's Rod!
In a rather mood-swinging moment, Nanachi tries giving Reg a Cooldown Hug when overcharging him with Idolfront's electricity caused him to become a violent berserker machine. It works and Reg returns to normal. Nanachi claims that he reacted to their voice, only for Reg to blush and say that actually it was their fluffiness... and we see that his pants are pitching a tent. An embarrassed Nanachi proceeds to slap him.
At one point when seeing Bondrewd's new form after taking the blessing of the Abyss, Nanachi proceeds to quip "Don't you think he looks cuter now?". This, jarringly, comes right before the revelation of Prushka having being turned into a cartridge.
When Faputa returns to Iruburu thanks to the hole blasted by Reg's Incinerator, she makes a very terrifying declaration about how she is going to kill every village inhabitant for leeching off her mother and is going to start immediately. What takes the edge off this whole situation is that majority of the villagers have no idea what she is talking about due to the language barrier and are only happy that their supposed "Princess" has returned. The result is that when Faputa makes her move, her would-be victims run towards her in joy.
◊ to it:
