I Actually Opened the SSR Succubus Big Sister

Traveling to a parallel time and space, the virus is raging and ghosts are rampant! The only remaining human beings evolved into weapon masters and activated Horcruxes to fight at the age of 18! Lin Mu, who carries the doubling system, actually opened the ultimate Succubus Big Sister! Successfully kill Friday Jason and your experience points will be doubled! "Master, please reward me with a kiss~" Successfully eliminate the monster Godzilla and double the rare pills! "Master~ I'm working so hard, please give me a shoulder rub." What! Can you withstand an attack and rebound twice as much? ! Since everything can be doubled... Could it be possible to be a succubus... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.