can you parse and "tail" at once? (and if you can't why not?)

[Albretch Mueller <lbrtchx@gmail.com>]

 After generating a file with lines of text, I have to:
 1) parse some of those lines based on a pattern I know (no regex
necessary, just a FS path)
 2) once parsed from those lines I need the last n characters only
 I am trying to use a one liner like:
 cat "${IFL}" | grep "${DESC_DIR}" | tail -c+$_DESC_DIR
 but this one liner repeats the output and the tail

 Say the lines of text in IFL are:
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Uppsala_Algebra/45_16.3_45MEB5h5H9Y.description
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Uppsala_Algebra/46_17.1_LE_gl5RcDnY.description
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Göttsche/17_9jKzwoBGFs8.description
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Göttsche/18_plOUIOo91lI.description
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Göttsche/19_TJ7yAiq8gEw.description
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/Göttsche/20_UMBEgb14uqw.description

 I know the prefix:
[info] 123XYZ: /media/user/1234qwer/Algebraic_Geometry04/20231022040239/

 I need as output:

Uppsala_Algebra/45_16.3_45MEB5h5H9Y
Uppsala_Algebra/46_17.1_LE_gl5RcDnY
Göttsche/17_9jKzwoBGFs8
Göttsche/18_plOUIOo91lI
Göttsche/19_TJ7yAiq8gEw
Göttsche/20_UMBEgb14uqw
~
 lbrtchx