Current draw

I have a 1993 Buick Roadmaster 120,000 miles with 5.7 engine. My battery was draining overnight with everything off, so I did an engine off all lights etc. Off and got a 2.26 amp draw I started pulling fuses one at a time and observed that when I removed the fuse that has CLUST. Printed on the fuse box cover (15 amp) I got a normal draw of 0.1 amp draw.I was under the impression the CLUST meant cluster yet when I took the car out at night with that fuse removed the cluster lights and guages still were operating?So what does that fuse CLUST. Incorporate in the system? Thanks much.