This Hero Is Clearly Powerful, Yet Far Too Cautious

[Japanese-style Western Fantasy + cautious and prudent + scheming but low-key + wild assumptions + decisive and ruthless + slice of life + no System] After naturally breaking through to Gold rank and becoming a so-called peerless master, Lin Lei was living the good life... but all he wanted was to keep a low profile and enjoy a peaceful retirement. If he had to add anything to that wish, it would be for the cute and beautiful elven tavern keeper to stop introducing him to women of other races. Like goblins, catfolk, dragons, succubi... Huh?! There are tentacle monsters and slimes too? This... this is beyond ridiculous. Ridiculous just walked through the front door and made itself at home! Anyway, to keep his mind at peace, Lin Lei tries not to get entangled in karma. Whenever he kills a person or monster, he makes sure to scatter the ashes. He thinks things through before acting and never recklessly steps into danger. He keeps his trump cards hidden, uses secret techniques, and resorts to poison and drugs... Lin Lei stays as steady as an old dog until he makes his move, then he makes a sensation and vanishes without a trace. By his own plans, he would spend his days training in peace at the tavern alongside the elven proprietor. That was until one day, when the tavern keeper got restless and came back with a quest for him... “Fine, this time it's... rescuing a princess?” Lin Lei hadn't wanted to take it, but they were offering far too much as a reward~