Note: I am Junior to this guy, and he has the power to decide over my future in the company at least partly. This takes place in Germany.
The company I am working at encourages peer reviews which are made on online forms. These are only between the one giving feedback, and the one receiving it. They are not shared with anyone else. Also these are completely optional.
The Senior in question asked me several times via mail, chat and in person to fill out this form. I really don't want to. I don't have much nice to say, and this form is extremely long. It takes more than 15 minutes to fill out and I really don't feel like lying. If I am honest I fear it hurts my future with the company.
Question: How can I dodge this task, without him being mad at me. And without him noticing that it would have been bad feedback.
(I literally just told him I will "think about it")
(EDIT: I already did 9 forms for other colleagues, but even if I had all the time in the world I would not want to fill out this form for him)
(EDIT 2: I will write one specific example: Our boss told me to do something, like "Do this and show your personal skillset like x, y and z!" afterwards he (the senior in question) comes up to me as says "No do a, b and c, I know you can do x, y and z you don't have to prove it" If I tell him our boss said I should do x, y and z, he tells me "That is not open for discussion I know better what our boss wants from you!" ... I did not want to include this context in the beginning because it is very specific, and I wanted the question to be helpful for others as well)
(EDIT 3: Topic sabotaging: You need to trust me on this one, I could probably write an entire book about situations like this. I asked a different boss I get along with really well (he is for another team) and even he told be to be extra careful with this senior. The space in our company is limited, and if I as a junior can't keep up the the standards they have for seniors, I will be replaced by a senior sooner or later)