 If you liked
Yugami-kun ni wa Tomodachi ga Inai
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 ...then you might like
Class de 2-banme ni Kawaii Onnanoko to Tomodachi ni Natta
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Both series feature loner MC's who are kind of fine with being alone. Yugami however does not feel loneliness at all, while the MC Maehara in the other series does and befriends the female lead almost instantly.
Both series take place in high school and try to elaborate on the question what is friendship, interactions between male lead and female leads are fun, so I feel like they fall under similar themes you can check out.