Mixed drinks – cheong

Helloooooo, The other day i was making a mix drink and i made a blackberry cheong(sugar + fruit in an equal ratio) and as the night went on i realized it wasn’t as strong as i thought it was for the amount of alcohol i put in. Does the amount of sugar affect the ABV? I poured a quarter of a 1.75L bottle and it felt like a refreshing beverage and didn’t taste like liquor at all. Can the liquor eat all the sugar?