TL:DR – my husband has gone insane, how do I evacuate me & my kids safely?

My husband is very active online, & one day, he stumbled onto something called “neco arc.” Occasionally, he would randomly blurt out “burenyu” & giggle. I asked him what it was, & he told me it was a cat that had become a meme. He didnt stop however, he would continue to say “gurenyu” & giggle, sometimes in his sleep. He eventually started sitting at the table & would whisper ” give me a beam” & then “Nya!” Before snickering again.

One time I got out of bed to go to the toilet, & I heard him say “burenyu” right outside the door. I was freaked out, but stayed quiet. When I opened the door to go back to bed, he was lying in the same position he was before.

The last straw was when I visited his office, & every surface was covered with a print out of this cat. He had atleast a dozen figurines of it reenacting some scene. He was rocking on his chair saying “burenyu” & “Nyaga!” Whilst giggling.

I dont know what to do, I dont feel safe anymore, but I love him. I feel I need to take the kids & run though, but I’m worried he will find us. What do I do?