ogra@laptop:~$ apt-cache show ltsp-client
Description: LTSP client environment
The scripts needed to configure and boot an LTSP client.
DO NOT install this package on a regular machine, it is intended only
for installation inside a LTSP client filesystem.
how did you get it installed at all, the package checks if the environment it is being installed in is an ltsp chroot and refuses to install if /etc/ltsp_chroot doesnt exist.