 Buffy essayist Ian Shuttleworth writes that Amber Benson ( Tara ) has " the sweetest singing voice of all the lead players " , referring to " Under Your Spell " as " heavenly and salacious " ; author Nikki Stafford concurs , writing that Benson " has the most stunning voice , showing a surprising range " . Whedon acknowledged that the " lyrical , heavenly quality " of Benson 's voice led him to assign her the episode 's love song . Alyson Hannigan ( Willow ) was unwilling to sing much and her performance is " apprehensive " , according to Shuttleworth . He considers this an example of Tara 's quieter strength coming out in front of Willow 's showy demonstrations of powerful magic . Buffy studies scholar Rhonda Wilcox interprets Willow 's diminished role representing the show 's silence about Willow 's descent into addiction and darkness through the rest of the season . Benson remarked that Tara 's story arc is significant within the episode , starting out with ecstasy but soon recognizing the illusory circumstances surrounding her bliss and that " life can 't be perfect all the time " . 
