Rose and Lily Field

Rose and Lily Field summary:

One day, a truck ran over me, welcoming the sudden death, i woke up in a unfamiliar room.
Checking my appearance in the mirror considering there is a silver haired beauty… And in the nether region there are changes from mini size to extra-large size.
Apparently reincarnated in a different world. According to G.o.d i have a spear that can cause the downfall of humanity.
Therefore with this erection i will save the world.