Opinions regarding a slowburn

Need some opinions. I'm writing a fantasy series with a little bit of romance. The first book has a subplot of building the relationship between FMC and the MMC. There is some romantic tension but nothing physical. If you were reading a slowburn romance series, do you think a kiss (just a kiss) at the beginning of the second book would take away from the tension of slowburn if the two characters didn't officially get together until the end of the second book? Thanks!