with all my heart (Idol!Tanjiro X Idol!Zenitsu Fanfic)

■ COMPLETED ■ "Promise me! When we get older, we get married!" "W-what? M-married?" "Yeah! Cmon! Pinky promise!" "O-ok!" "Its decided now! Bye bye Tanjiro!" I wake up, sweating and panting. Who was that kid? Who did Tanjiro get engaged with? Read the book and find out! I do not own any of Kimetsu no Yaiba's characters...