They skipped this in the manhwa but in the novel it’s mentioned that at a certain point in the future the system will kill anyone who worry for him so he needs to get them to stop caring about him for their own safety
It’s impossible for him to get drunk because his insanely high mental strength from how much suffering he’s been through to put into perspective the reaching a 9 in a stat is basically reaching the peak and nearly impossible to increase beyond
The reason why he wants to lose is because for a later the main boss of it will be random if he wins this was explained in the novel but was cut out of the manhwa because this adaptation is ass and did not do it justice