The lifeforce in the lantern, is it?

Hey guys, I had one question regarding the souls of whom Thresh has trapped inside his lantern for all of eternity. Yes this includes are beloved Senna aka Lucian's wife. Are they forced to provide their life force (assuming that the green bubble thingy that the lantern gives to teammates is their life force) to thresh's teammates? Are they forced to protect Thresh's teammates? For example, teammates such as top laner, the adc etc. Is that something against their will? And from a hypothetical point of perspective, how would the champion engulfed in the green bubble feel like, I mean how does that stuff feel like when it's around you, keeping in mind it does protect the person from damage but still...Feels weird I guess?