How do I reject him faster instead of wasting my time on him?

basically he texted me first, so i texted back. talked for some time, he then wanted to go in a relationship with me. he told me how he never dated anyone bc they always rejected him, how he was scared that i was going to block him like them, how he felt insecure and believed i was nice, and so on and literally made me feel bad for him. I don't know if its gaslight but. so i didn't have the heart to reject him, i just told him there might be a chance between us, so i basically led him on. i just keep leading him on, he'd flirt but i wouldn't really so call flirt back, but i accepted him. but i really dont and am not interested in him. whats the best way for him to stop texting me without hurting him again, like how he was hurt in the past. i feel bad for leading him on. but id feel even worse to reject him given his past experience.

How do I reject him faster instead of wasting my time on him?
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