One of the best ways to reduce the carbon footprint is to convert second-generation biomass (s-BM) into fuels in oil refineries. However, s-BM is not suitable for conventional processing. To circumvent this problem, we first converted s-BM under mild conditions in the presence of acetone into a stable non-corrosive liquid, which we call bio-petroleum (BP). This process did not result in carbon loss, and the BP exhibited a reduced number of parallel reactions during its further transformation. This article describes the results of co-processing BP with vacuum gasoil up to high amounts (75 wt%) through fluidized catalytic cracking (FCC). A small amount of unwanted coke was observed, while 70–79% green carbon was incorporated into products like LPG and gasoline. Feed mixtures up to 35 wt% BP produced drop-in fractions of green hydrocarbons to LPG, gasoline, and petrochemical feedstocks. With higher amounts of BP, the mixtures produced high added-value products. We employed this approach as a starting point to produce carbon-neutral fuels.