+Beanie's Corner it's not really incest since their relationship are up to the viewers but I guess since this song is about hiding the fact that the two lovers are gay, in this case it's about them being twins I guess?
Bethartsy 02 Len; "Our love can't be together, because we are siblings" Rin; "It doesn't matter as long as we are together" Something along those lines.
alpak Len kinda said that our loved cant be together cuz we are brother and sister but rin just said that it's dosent matter as long as they were together : D