If you are confused by these writings like; 4LL, 4BL, and 4GL, actually... that's are the codes for the genre that the character is in.

FOR YOUR INFORMATION ONLY.

— 4LL, Is a term for 'for everyone'. Which means this character is for everyone, no matter gender or anything else. — 4BL, Is for 'for Boy Love'. You must have heard this term. Yes, it's the love of both male. — 4GL, For this one, this is the term for 'for Girl Love'. A term of love between a female and a female.