I Think So Too. In The Beginning As Well, Natsuka Didn't Believe That They Switched Bodies So At That Moment He Could Have Played It Off As A Joke And Their Relationship Would Not Have To Be Compromised. But I'm Still Unsure If They Actually Switched Bodies But I'm One Of The Few Who Don't Support Seno In His Endeavors.
Read the Volume 2 and you will know why Seno deserve to be loved why he do that!
It's Second Nature To Me Now Haha Result Of An Occupational Hazard :)

OOOOH HE IS FUCKED IF HE WAS LYING (and for 2 fucking months too), trust will be destroyed. seno knows firsthand that natsuka was INSANELY in love with hakushima and if seno pretended to be someone he's not just to earn natsuka's love, i don't think it was worth it at all. also its wrong to manipulate the emotions of a grieving person and take advantage of the situation