Probably the saddest thing about our lives is that everything comes to an end. A few days ago, sadly, one of the best things that happened to the internet ended. To be more specific, Maru, the most well-known cat on YouTube that blessed our eyes for over a decade, crossed the rainbow bridge. Now he’s trying to squeeze himself into boxes in heaven, while we grieve his loss here on Earth.
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Sadly, even the best things in the world come to an end at one point or another
Image credits: I am Maru. / YouTube
The passing of Maru, beloved cat from YouTube, proves it
Image credits: I am Maru. / YouTube
His owners reported that on the morning of September 6th, Maru crossed the rainbow bridge
Image credits: I am Maru. / YouTube
At the end of summer, Maru started feeling very off — not eating, breathing heavily
Image credits: I am Maru. / YouTube
His owners, worrying about his well-being, took Maru to the vet
Image credits: I am Maru. / YouTube
It was found out that he had cancer, which ended up being fatal
Image credits: mugumogu / Sisinmaru
To be more specific, he had lung adenocarcinoma, which is a type of lung cancer
Image credits: mugumogu / Sisinmaru
Maru was well-known for his funny and endearing videos of trying to squeeze into boxes
Maru, a cat well-known on YouTube, passed away on September 6th, 7:15 a.m.
The cat’s owners reported that in the last week of his life, Maru had become very sick. In the middle of August, he started to lose his appetite, leaving a third of his rice uneaten.
Before you ask, yes, cats can eat rice. If it’s well-cooked, plain, and fed in conjunction with a balanced commercial cat food, it’s absolutely fine for them. In fact, some vets even recommend feeding it to the felines when they suffer from diarrhea or stomach bugs, as fiber helps harden the stool.
Besides unfinished rice, there was nothing about the pet to worry about. He was more than happy to eat chicken, so his appetite wasn’t completely lost.
Until his breathing became weird, seemingly forced, irregular. So, the owner took him to the hospital, where vets took an X-ray of his chest. It showed that both of Maru’s lungs were white and inflamed. Then, an echo test was issued, as there was a suspicion of lymphoma (cancer of the lymphatic system).
Additionally, water was found in the poor cat’s lungs, and it was decided that due to the blood oxygen level being only 74%, the cat could not withstand a CT scan under general anesthesia.
Image credits: mugumogu / Sisinmaru
In the end, it was found out that it was indeed cancer. Only, not lymphoma as previously suspected, but rather lung adenocarcinoma, or simply put, lung cancer. The thing was that anti-cancer medicine is not effective for this type of sickness. The owners were told that Maru’s days were numbered. His last one ended up being September 6th, 2025.
Maru, in Japanese まる, was a male Scottish Straight cat born on May 24th, 2007, making him 18 years old at the time of death. As the Japanese version of his name suggests, he lived in Japan with his owner, who uses the pseudonym “Mugumogu.”
At the beginning of 2008, Mugumogu started posting videos on the Maru YouTube channel. For example, some footage of Maru attempting to squeeze into a cardboard box as part of a YouTube challenge, which, after its virality, became a signature move.
In total, these videos have been viewed over 577 million times. At one point, Maru held the Guinness World Record for the most YouTube video views of an individual animal, and he has been described as the “most famous cat on the internet.” Pretty impressive, isn’t it?
So, no wonder that when the news of Maru’s passing spread, netizens went into full grieving mode. This cat was the internet’s darling, and losing such a precious gem was another hit to an already wild year.
After the loss of internet’s darling, netizens didn’t hide their grief
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