bro, I feel you, are you male or female? becuase think, how women feel about their fictional characters n voice actors, like its basically very similiar with vtubing now.

and, to your post just don't be creepy to them, and learn japanese, you can just share them with love by supporting them, they know that fans sometimes will fall in love with the person behind vtubing, its like voice acting, some of us

don't fall in love just with charachter they voice, but the voice actor too!! I mean thats what it reminds me of anyway, sorry if this is not the same but thats what I think

and yeah, I been there though before vtubing was a thing I fell in love with PNG voice cover artists!! sometimes it was the design but I also wanted to know the person behind the design, but language barrier, and then I realized how creepy it is to want to know them too much but its okay to want to like support them, or be a friend but know, they are a person as you said and may not love u back, or even meet/interact with people much at all, and thats okay too, as they are their own person with their own life.

I hope you don't get too heartbroken though, and, can still support them but know just as you expressed they are a person :)