"There are two types of Thai men," said Chanthong. "Those who work with tourists and those who have come down from the mountains and never come into contact with them. Most Thai men have the same respect for Western women as they do for Thais, but some men see European women topless on the beach and think it is easy to have sex with them. I even have friends who come down from Bangkok and ask if I can find them a European woman to have sex with. I say it is not like a piece of cake. They don't understand that. I suppose it's the same as the European men who come here thinking Thai women are easy."
Koh Samui is increasingly becoming a tale of two cities. While it is still possible to rent a beach hut like the one Katherine had stayed in for US$15 a night, they are becoming a rarity. In their place are multi-million-dollar homes and five-star spa resorts. In the next six months, around 20 upmarket health spas are due to open.
Although the permanent population of the island is just 40,000, it now draws nearly 1 million tourists every year. Thailand as a whole hopes to increase its tourist numbers from 14 million to 20 million by the end of 2008.
Unless there are some controls, however, on the relentless overdevelopment of islands such as Koh Samui, many locals fear it will not only spoil the area and the environment, but also lead to an increase in crime and corruption.
There is already endemic corruption among police and government officials in Thailand. And, despite Samui's increasing levels of crime, it has only 15 tourist police and a regular force of 200.
Despite the myth peddled in holiday brochures and assurances from police and politicians that Koh Samui is safe, in the past eight weeks, there have been at least five murders, more than 20 robberies, the same number of violent assaults and around 15 gun-related incidents.
There have been at least two more reported rapes on the island since the beginning of December. One involved a 26-year-old British woman who was allegedly raped by two men in the island's busiest resort of Chuweng. The two fishermen charged with Katherine's murder have been linked to this attack. Photographs of them have been sent to the victim but sources in Thailand have said the men vehemently denied any involvement. In the other case, a 12-year-old Swedish girl was allegedly raped by a man who worked in the resort where her family was staying.
Although these are the only known reported rapes, the true level is thought to be much higher. Police in Thailand tend to turn a blind eye to violence in relationships, even if that relationship is little more than a one-night liaison on the beach.
Katherine's murder may focus minds. It may just bring a little more control over the rapid development of the island and its deteriorating infrastructure.
Paiant Pangha, a driver in the area, said many ordinary Thais felt their island was being taken away from them and destroyed for ever. "This was once a beautiful island, but it has lost so much of its charm. It resembles a massive construction site, as every inch of land is sold off to developers to build more luxury resorts, with no regard whatsoever for the environment or the natural ecology."