To follow up on NinjaMushi's excellent review which you should absolutely read if you're considering reading this abomination of a manga, here are some more things Himitsu no Reptiles gets wrong:
1. handling amphibians without washing hands with dechlorinated water: amphibians like frogs absorb chemicals including water (but also including deadly toxins) through their skin so before holding them it is IMPERATIVE that you spritz your hands down with dechlorinated water lest you risk transferring some dangerous chemicals into their bodies.
2. saying adult pacman frogs can live in a 7x10 inch container: no. adults need at LEAST a 10 gallon aquarium, and bigger is better.
3. not even giving pacman frogs loose substrate to burrow in: this one just hurt my heart. horned frogs LOVE to burrow almost as much as they love food (more on that in a sec) and putting them on a mat for their entire life is just abuse. it's a totally natural behavior for them and they should be allowed to express it.
4. not even providing the frogs with hiding spots: jesus christ how wrong can you get? just a fake plant would've sufficed.
5. saying the frogs can live on preprepared foods: aaaaand this might be the worst one. frogs need INSECTS. LIVE INSECTS. just like the geckos. it can have the paste foods as like an occasional treat like it can have fish and pinkies as treats, but its staple diet needs to be gut loaded, calcium/vitamin-dusted INSECTS. sorry, gujira.
so in conclusion i pray to god nobody reads this manga and thinks reptiles are actually this easy, buys one, uses this as a care sheet, abuses it, and winds up killing it. thank you for reading.