Thanks to James Holderness for helping me get out of triple digits!

Thanks to James Holderness for helping me get out of triple digits!

Befunge-98, 109 bytes (FUNGE / ANY)

:5%!2>j#4_;\$&\#;\:0`!#@_:::88*/88**-\88*/2%*442**+,:88*/:2/-88**-\1+:5%!2>j#4_;442**3k:4k,#;:55*%!2>j#4_;a,; 

Try it online!

(255 - (115 + 109)) / 255 = 12% compression

:5%!2>j#4_;\$&\#;\:0`!#@_ Get input if it is available, else end program :::88*/88**-\88*/2%*442**+, Output the current input character (or a space, if the mask dictates so) :88*/:2/-88**- Throw away current mask bit \1+ Swap loop iterator to top of stack, increment it :5%!2>j#4_;442**3k:4k,#; If iterator % 5 == 0, print five spaces :55*%!2>j#4_;a,; If iterator % 25 == 0, print newline character 

Theoretically this can print any sequence of 5x5 ascii art.

Befunge-98, 109 98 bytes (FUNGE / ANY)

:5%!2>j#4_;\$&\#;\:0`!#@_:::'@/'@*-\'@/2%*' +,:'@/:2/-'@*-\1+:5%!2>j#4_;' 3k:4k,#;:55*%!2>j#4_;a,; 

Try it online!

(255 - (115 + 98)) / 255 = 16% compression

:5%!2>j#4_;\$&\#;\:0`!#@_ Get input if it is available, else end program :::'@/'@*-\'@/2%*' +,  Output the current input character (or a space, if the mask dictates so) :'@/:2/-'@*-  Throw away current mask bit \1+ Swap loop iterator to top of stack, increment it :5%!2>j#4_;' *3k:4k,#;  If iterator % 5 == 0, print five spaces :55*%!2>j#4_;a,; If iterator % 25 == 0, print newline character 

Theoretically this can print any sequence of 5x5 ascii art.

Thanks to James Holderness for helping me get out of triple digits!

Befunge-98, 109 bytes

Befunge-98, 109 bytes (FUNGE / ANY)