Screamer Pink vs Asmodeus Red

How close are they?

ΔE 15.5, loose: different enough that you should pick on purpose. Asmodeus Red is noticeably lighter, warmer than Screamer Pink.

Can I use Asmodeus Red instead of Screamer Pink?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Asmodeus Red is noticeably lighter, warmer than Screamer Pink.

Can I use Screamer Pink instead of Asmodeus Red?

The same difference applies the other way round: Screamer Pink is noticeably darker, 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.