the light you want to remove will either have a permanent Live and Neutral into it from another room and then a Permanent Live and Neutral to the next light in the living room with a switch live and Permanent live down to the switch or a Permanent live and Neutral from the first light and then a Permanent Live and Neutral to another room again with a switch live and permanent live down to the switch...
the fact this light i controlled by it own switch makes this trickier for you...
That is an AMAZING insight. Have you been to his house then, or do you have some magic powers?
This may not be a loop in at light system. It could be loop at the switch, or there could be one of those big brown junction boxes under the landing floor.
Lets wait and see what there really is, the answer will be different for each.