ΔE 17.4, loose: different enough that you should pick on purpose. Vampiric Purple is noticeably darker, more saturated, warmer than Fairy Blood.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Vampiric Purple is noticeably darker, more saturated, warmer than Fairy Blood.
The same difference applies the other way round: Fairy Blood is noticeably lighter, more muted, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Fairy Blood on the colour wheel See Vampiric Purple on the colour wheel
All matches: Fairy Blood equivalents · Vampiric Purple equivalents