Sorry to labour the point but perhaps someone from Customer Care could clear up the issue online whether used anal toys can be returned (rather than take the word of a Forum user)?
Also, what is a ‘better sex product’? The search I have just done on LH comes up with only two products, Zuyosa Alphaboost Supplement and Earthly Body Trio 3-in-1 Mini Massage Candles (which are great by the way).
I would have thought a lot of what LH sells are ‘better sex products’
You will need to contact Customer Care. It is very unlikely that they’ll answer you here. Email/live-chat/phone them, and then come report back what they say. 
(I can answer the Better Sex thing, but if you’re contacting Customer Care you may prefer theirs 
)
Don’t leave us hanging buddy. What did they say?
Is it possible to buy a prostate toy, stick it up your bum, decide it’s rubbish, (wash it), and return it for a refund?
Edit: For those who can’t bear to wait any longer, yes it is possible. 
You’d need to Contact them via Live Chat, Customer Care won’t see the questions posted here.
Anal toys are Sex Toys and can therefore be returned under the Sexual Happiness Promise
Here are the Better Sex categories:
https://www.lovehoney.co.uk/sex/better-sex-for-her/
https://www.lovehoney.co.uk/sex/better-sex-for-him/
https://www.lovehoney.co.uk/sex/better-anal-sex/
https://www.lovehoney.co.uk/sex/better-oral-sex/