Lyric discussion by SliverLines 

I took this song to mean as maybe it's the beginning of a new relationship but she's guarded because she really likes him and isn't sure how long it's going to last. I think she's also hoping that he'll break down her defenses and admit how he feels for her first so she can be open about her feelings and they can finally call it love.

I think you're right; that's what I thought, too, especially since the song says:

"How long, 'til we call this love?"

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