using sed and pstree to display the type of terminal being used

using sed and pstree to display the type of terminal being used

I've been trying to display the type of terminal being used as the name
only. For instance if I was using konsole it would display konsole. So far
I've been using this command.
pstree -A -s $$
That outputs this.
systemd---konsole---bash---pstree
I have the following that can extract konsole from that line
pstree -A -s $$ | sed 's/systemd---//g;s/---.*//g' | head -1
and that outputs konsole properly. But some people have output from just
the pstree command that can look like this.
systemd---kdeinit4---terminator---bash---pstree
or this
systemd---kdeinit4---lxterminal---bash---pstree
and then when I add the sed command it extracts kdeinit4 instead of
terminator. I can think of a couple scenarios to extract the type of
terminal but none that don't contain conditional statements to check for
specific types of terminals. The problem I'm having is I can't accurately
predict how many non or non-relative things may be infront or behind of
the terminal name or what they will be nor can I accurately predict what
the terminal name will be. Does anyone have any ideas on a solution to
this?