what is this mysterious character in kernel main function? How can i remove it?

I am trying to create my own kernel following the link https://wiki.osdev.org/Bare_Bonesthe author has mentioned that " followed by some mysterious character. "Why is this character occurring? How can I remove it?

I am using the kernel.c file, just changed the kernel main to print ASCII char.

void kernel_main(void) {    terminal_initialize();    terminal_writestring(" ____                         ___  ____");            terminal_putchar('\n');    terminal_writestring("|  _ \\ _   _ _ __ ___   __ _ / _ \\/ ___|");            terminal_putchar('\n');    terminal_writestring("| |_) | | | | '_ ` _ \\ / _` | | | \\___ \\");            terminal_putchar('\n');    terminal_writestring("|  __/| |_| | | | | | | (_| | |_| |___) |");            terminal_putchar('\n');    terminal_writestring("|_|    \\__,_|_| |_| |_|\\__,_|\\___/|____/");            terminal_putchar('\n');}

Here is my result