# x86-16 machine code, IBM PC DOS, <del>13</del> 10 bytes

    00000000: b04c cd29 0c20 3403 ebf8                 .L.). 4...

Listing:

    B0 4C		MOV  AL, 'L' 		; start off with capital L
    		PRINT:
    CD 29		INT  29H 			; write to console
    0C 20		OR   AL, 020H 		; lowercase it
    34 03		XOR  AL, 3 			; swap between 'l' (0x6c) and 'o' (0x6f)
    EB F8		JMP  PRINT 			; loop forever

A standalone PC DOS executable COM program. Output to console.

**-3 bytes thx to @nununoisy's very clever use of `XOR` to swap between `l` and `o`.**

Runtime:

[![enter image description here][1]][1]

*Forever and ever...*


  [1]: https://i.sstatic.net/7AnHb.png