HE was sitting on my chest, purring, his eyes boring into mine. It was 5.30am. We didn't know but he had just over three hours of his happy carefree life remaining.
He would eat only one more meal, summon up a final purr and miaow, cast a disdainful goodbye glance at his sister and deliver a friendly farewell "bop" before taking his last breath.
My first ever boy cat, he arrived, along with his sister Belle, from a rescue centre at just six weeks old, their mum having been run over a month previous.
He was named Sebastian after a cat my parents had when I was born and that meant his sister would be Belle in tribute to one of my favourite bands (Belle and Sebastian).
Dinah at the pet rescue home had called him - the runt of a litter of five - Lucifer and marvelled at his ability to splay himself across the communal food dishes, thus denying the other much bigger kittens any food at all.
Before long he was king of the hill (in his head), keeping guard from the back garden wall and on one occasion atop a near neighbour's chimney breast. He made friends with most of the street, regularly entering their houses and being given treats or stealing whatever he fancied - a make-up brush being one of his more unusual choices.
He overcame various illnesses, including a strain of human-type flu, with little fuss, purring through whatever crisis befell him.
He was, without doubt, the friendliest, most positive cat I have ever known - you could never move without being followed by Seb, ever hopeful that he would be given something better than what he already had.
He lived for the "m" of the moment and, whether that proved fruitful or not, was always on to the next thing by the "o".
He was diagnosed with a tumour in his back leg more than five years ago, but happily continued his life as normal, his gradually worsening limp not really bothering him, except in stopping him from leaping quite as high.
Fights with his sister - and unwelcome cat visitors - did not stop, he yowled at the door to be let out at all hours and shouted the place down in the middle of the night, every night, when he awoke with fright to discover no-one else was downstairs with him.
Then at Christmas 2021 his cancer started to grow and his limp got worse. There was more medication but he still went about his daily business in the same way.
Then, in March last year, I returned home to discover he had cut open his tumour. There was blood all over the carpet and stairs and a midnight visit to the out-of-hours vet was necessary to stop the flow.
The vet was astonished that he remained so placid while having his wound treated and dressed. No pain got him down and that trend continued in subsequent visits until on April 26 when, in for a bandage change, came the news that his blood wouldn't clot and there was no more they could do.
It was heartbreaking to look at his hopeful little face as I held him, talked to him, stroked him and told him how brave he was as the vet put him to sleep.
On that Tuesday morning, four weeks short of his 17th birthday, having jumped onto the bed for a 5.30am stroke for what would turn out to be the last time, he purred to the end, until the very second that Belle and Sebastian were inevitably reduced to Belle.
I left through a side door at the vets, unable to face the walk through reception, knowing we had helped him live the best life possible.
He achieved much of his happiness himself though and if I didn't know before that you could learn so much from a cat about positivity, never giving up, always striving for more and usually being rewarded for your efforts, I do now.
RIP little man.