Little is known about their personalities since they appear sporadically throughout the series as comic relief, mainly due to encountering a few of Stitch's cousins who annoy or torture them in some manner. They love each other and enjoy having fun.
Charles is slightly arrogant about his job, often telling people he is a vice president. Mary's personality seems to be rather romantic, often telling people they are on a honeymoon and trying to take in the sights. Charles seems out of shape, as he was unable to keep up with Mary on a nature hike. He also enjoys taking pictures.
Role in the series
They reappeared in "Kixx", where they were seen walking along on a nature trail and Charles threw his water bottle away, causing the water from it to trickle out and touch Kixx's pod, activating him. He later attacked the two.
In "Yaarp", they were taking pictures of Kauai and buying fruit from Mrs. Hasagawa before Yaarp blasted their eardrums with his megaphone, making them temporarily deaf. They later tried to buy a new camera at an electronics store, only for Yaarp to destroy the store. They then went to the same cave where Yaarp was hiding, while Pleakley went in to capture Yaarp. When Pleakley heard footsteps approaching, he turned on his vacuum-sucking device meant to capture Yaarp, but accidentally stole Charles and Mary's clothes as a result, though he gave them back. Later, when the cave collapsed, they ran out. They then went to a museum for peace and quiet before Gantu showed up and started attacking, causing them to complain to the mayor.
In "Spats", Lilo tried inviting them to Jumba and Pleakley's Bed and Not Breakfast to help make money for Lilo, but they declined, saying it was too weird for them. Later, Spats zapped them with his argument-inducing ray and caused them to get into a fight, with Mary slapping Charles for getting too fresh with her and Charles saying it was their honeymoon. Later on, they watched the match between Suga Mama and Gantu and counted to ten, ending the belligerence between them as that was the cure to Spat's argument-inducing ray.
- As stated by executive producer Jess Winfield on his TV Tome Q&A thread, Charles and Mary are based on fellow executive producer Bobs Gannaway and his wife.
- Despite them saying in "Yaarp" that they'll never come back to Hawaii due to some aliens ruining their honeymoon, they reappeared in "Babyfier", "Drowsy", "Slick", "Retro", "Spats", and "Snafu".
- It is possible they returned because they either forgot about it, gave Hawaii another chance, or said episodes chronologically took place before "Yaarp".
- In "Spats", after being hit by Spats' argument ray, Mary slapped Charles after she accused him of getting fresh with her, only for him to reply that it's their honeymoon.
- It is possible this episode chronologically took place before "Yaarp", serving as a continuity.