Attaching virtual session (e.g. SSH) to seat

[Nils Kattenbeck <nilskemail@xxxxxxxxx>]

I am logging in on a PC using SSH and need to access some peripherals
which are attached to seat0.
loginctl shows that my session is not attached to any seat:

SESSION  UID USER      SEAT TTY
     50 1000 septatrix      pts/0

The devices are added to the seat using udev rules
and I explicitly want to avoid making the device world read-/writeable
or adding it to a group.
Reading through the man pages for systemd-logind, pam_systemd etc
did not lead me anywhere helpful but only confirmed the fact
that virtual sessions are not assigned any seat by default.
However I was unable to find information on how it is determined
if a session is "virtual" or whether it can be configured for pam/logind/udev...