We'd be here for days if I listed them all

• Ash x Gou (Anipoke)
• Ash x Kiawe (Anipoke)
• Ash x Gladion (Anipoke)
• Raihan x Leon (Pokemon)
• Red x Blue (Pokemon)
• Ethan x Silver (Pokemon)
• Steven x Wallace (Pokemon)
• Sonia x Nessa (Pokemon)
• Rin x Hanayo (Love Live)
• Nico x Maki (Love Live)
• Nozomi x Eli (Love Live)
• China x Riko x You (LL Sunshine)
• Yohane x Dia (LL Sunshine)
• Yohane x Riko (LL Sunshine)
• Kanan x Mari (LL Sunshine)
• Yuu x Anyone (LL NijiGaku)
• Rina x Ai (LL NijiGaku)
• Kanata x Emma (LL NijiGaku)
• Emma x Karin (LL NijiGaku)
• Kasumi x Shizuku (LL NijiGaku)
• Tamaki x Sougo (Idolish7)
• Riku x Iori (Idolish7)
• Yamato x Nagi x Mitsuki (Idolish7)
• Yuki x Momo (Idolish7)
• Henri x Masato (Precure)
• Akira x Yukari (Precure)
• Hikaru x Lala (Precure)
• Elena x Madoka (Precure)
• Nodaka x Hinata (Precure)

And so so many more