(Just in case you didn't read the ending of the chapter 1 here's a notice and more detail.)
Strength: Increases and determines your physical abilities such as Strength, Speed, Durability.
Vitality: Determines your Stamina / Mana and How many hits you can take without pain, Increases your health.
Agility: Increases his perception of time and thought processing allowing him to view others in slow motion.
Intelligence: Increases the users Mana as well as his recovery of it, It also increases the effectiveness of magic and skills, It also increases the users memory meaning he at a high enough intelligence can memorize an entire book in seconds and perfectly memorize spell books.
Luck: Increases the users luck in situations and in general it allows him to get into accidental perverted situations and 50/50 not get slapped, Gets a better chance at getting better items, Increases the users chance for critical hits as well as Increases his luck for stuff like School, Relationships, Other people, ect the best example is if he wanted to stay home and grind levels from school normally it wouldn't work or happen but with a high enough level the next day it close do to an accident for a day.
Sense: Increases your 5 Senses as well as grants a sixth sense at Level / Number 20 anyway, At a high enough level he can see in the dark as if it were day can also see through any visual obstructions view 75 Kilometers away, Can smell better than canines and would put most trained dogs to shame and even smell Poison, Can hear someones heartbeat and cameras from 15 meters away and hear through and entire building and possibly use echolocation, Grants a sixth sense allowing him (at a high enough level grant Instinctive Reaction and Precognition up to 6 seconds.) And sense others emotions such as bloodlust or vibrations in the air.
STAT SKILLS
Stat skills mean skill you could gain from leveling up certain stats to a certain level such as "Sense" stat to lv 85 for the skill <Universal Sense> or leveling up "Agility" for <Time Slow> and ect, ect.
